feat(kernel): P31 step1 occupation dialogue response bias

- Occupation.biasResponse: deterministic pure remap over Sim.responseFor;
  no occupation = byte-identical pass-through (all intents x personalities).
  farmer AskHelp Refused->Helpful; fisher SmallTalk Reserved->Friendly;
  peddler SmallTalk Reserved->Bargaining; scholar Joke fully overridden to
  Reserved (documented total-override semantics, opposite of personality).
- Sim.responseFor made public (same pure function, reused as the base path).
- Sim.chooseDialogueWith: extracted body of chooseDialogue with an injectable
  respond function; chooseDialogue keeps identity semantics unchanged.
- Sim.appendAnnal made public for the upcoming story annal writes.
- 9 new kernel tests (92 -> 101); performance digest unchanged.

4 files changed, 193 insertions, 4 deletions

diff --git a/src/LivingVillage.Kernel.Tests/LivingVillage.Kernel.Tests.fsproj b/src/LivingVillage.Kernel.Tests/LivingVillage.Kernel.Tests.fsproj
index dea8314..6924012 100644
--- a/src/LivingVillage.Kernel.Tests/LivingVillage.Kernel.Tests.fsproj
+++ b/src/LivingVillage.Kernel.Tests/LivingVillage.Kernel.Tests.fsproj
@@ -14,6 +14,7 @@
     <Compile Include="M6aTests.fs" />
     <Compile Include="DailyTaskTests.fs" />
     <Compile Include="TradeBiasTests.fs" />
+    <Compile Include="OccupationBiasTests.fs" />
     <Compile Include="PerformanceTests.fs" />
   </ItemGroup>
 
diff --git a/src/LivingVillage.Kernel.Tests/OccupationBiasTests.fs b/src/LivingVillage.Kernel.Tests/OccupationBiasTests.fs
new file mode 100644
index 0000000..76e02f3
--- /dev/null
+++ b/src/LivingVillage.Kernel.Tests/OccupationBiasTests.fs
@@ -0,0 +1,146 @@
+namespace LivingVillage.Kernel.Tests
+
+open Microsoft.VisualStudio.TestTools.UnitTesting
+open LivingVillage.Kernel
+open LivingVillage.Kernel.Sim
+
+module private BiasHarness =
+
+    /// 覆盖 responseFor 全部分支的两个人格样本：
+    /// 外向+诚实（E>=0.5, H>=0.4）与 内向+不诚实（E<0.5, H<0.4）。
+    let outgoing = { Drive = 0.5f; Aggression = 0.2f; Extraversion = 0.8f; Honesty = 0.9f; Greed = 0.3f }
+    let withdrawn = { Drive = 0.5f; Aggression = 0.2f; Extraversion = 0.2f; Honesty = 0.1f; Greed = 0.3f }
+    let grumpy = { Drive = 0.5f; Aggression = 0.8f; Extraversion = 0.2f; Honesty = 0.1f; Greed = 0.3f }
+
+    let atNpc (id: int) (world: World) : World =
+        let npc = world.Npcs.[id]
+        { world with Avatar = { world.Avatar with Pos = npc.Pos } }
+
+[<TestClass>]
+type OccupationBiasTests () =
+
+    // ---- 无职业 = 既有 responseFor 输出逐字节不变 ----
+
+    [<TestMethod>]
+    member _.NoOccupationReproducesTheHistoricResponsesForEveryIntent () =
+        for intent in [ SmallTalk; AskHelp; OfferTrade; Joke; Apologize; Provoke ] do
+            for personality in [ BiasHarness.outgoing; BiasHarness.withdrawn; BiasHarness.grumpy ] do
+                Assert.IsTrue(
+                    Sim.responseFor intent personality = Occupation.biasResponse None intent personality,
+                    $"no-occupation bias must be identity for {intent}")
+
+    // ---- 农夫 AskHelp：Refused → Helpful（求助更友好）----
+
+    [<TestMethod>]
+    member _.FarmerAskHelpTurnsRefusalIntoHelpfulness () =
+        // 不诚实村民对常人 Refused，对农夫给 Helpful
+        Assert.AreEqual<DialogueResponse>(Refused, Sim.responseFor AskHelp BiasHarness.withdrawn)
+        Assert.AreEqual<DialogueResponse>(Helpful, Occupation.biasResponse (Some Occupation.Farmer) AskHelp BiasHarness.withdrawn)
+        // 本就 Helpful 的路径不变
+        Assert.AreEqual<DialogueResponse>(Helpful, Sim.responseFor AskHelp BiasHarness.outgoing)
+        Assert.AreEqual<DialogueResponse>(Helpful, Occupation.biasResponse (Some Occupation.Farmer) AskHelp BiasHarness.outgoing)
+
+    // ---- 渔夫 SmallTalk：Reserved → Friendly（聊天气鱼汛，冷场变热络）----
+
+    [<TestMethod>]
+    member _.FisherSmallTalkWarmsUpAReservedVillager () =
+        Assert.AreEqual<DialogueResponse>(Reserved, Sim.responseFor SmallTalk BiasHarness.withdrawn)
+        Assert.AreEqual<DialogueResponse>(Friendly, Occupation.biasResponse (Some Occupation.Fisher) SmallTalk BiasHarness.withdrawn)
+        Assert.AreEqual<DialogueResponse>(Friendly, Sim.responseFor SmallTalk BiasHarness.outgoing)
+        Assert.AreEqual<DialogueResponse>(Friendly, Occupation.biasResponse (Some Occupation.Fisher) SmallTalk BiasHarness.outgoing)
+
+    // ---- 货郎 SmallTalk：Reserved → Bargaining（三句不离买卖，更易进讨价还价）----
+
+    [<TestMethod>]
+    member _.PeddlerSmallTalkSlidesIntoBargaining () =
+        Assert.AreEqual<DialogueResponse>(Reserved, Sim.responseFor SmallTalk BiasHarness.withdrawn)
+        Assert.AreEqual<DialogueResponse>(Bargaining, Occupation.biasResponse (Some Occupation.Peddler) SmallTalk BiasHarness.withdrawn)
+        // 外向村民本就 Friendly，不被货郎偏差改写
+        Assert.AreEqual<DialogueResponse>(Friendly, Occupation.biasResponse (Some Occupation.Peddler) SmallTalk BiasHarness.outgoing)
+
+    // ---- 书生 Joke：完全覆盖为 Reserved（与 personality 相反的确定性偏差）----
+    // 语义说明：书生讲笑话走「完全覆盖」——无论村民性格如何，回应一律 Reserved。
+    // 刻意不做概率偏向（禁随机）；反差感即设计意图（design §5）。
+
+    [<TestMethod>]
+    member _.ScholarJokeIsAlwaysReservedRegardlessOfPersonality () =
+        Assert.AreEqual<DialogueResponse>(Amused, Sim.responseFor Joke BiasHarness.outgoing)
+        Assert.AreEqual<DialogueResponse>(Reserved, Sim.responseFor Joke BiasHarness.withdrawn)
+        for personality in [ BiasHarness.outgoing; BiasHarness.withdrawn; BiasHarness.grumpy ] do
+            Assert.AreEqual<DialogueResponse>(
+                Reserved,
+                Occupation.biasResponse (Some Occupation.Scholar) Joke personality)
+
+    // ---- 偏差只作用于各自的签名意图，其余意图原样穿透 ----
+
+    [<TestMethod>]
+    member _.BiasOnlyAppliesToTheSignatureIntents () =
+        // 农夫：仅 AskHelp 受偏差
+        for intent in [ SmallTalk; OfferTrade; Joke; Apologize; Provoke ] do
+            for personality in [ BiasHarness.outgoing; BiasHarness.withdrawn ] do
+                Assert.AreEqual<DialogueResponse>(
+                    Sim.responseFor intent personality,
+                    Occupation.biasResponse (Some Occupation.Farmer) intent personality)
+        // 渔夫：仅 SmallTalk 受偏差
+        for intent in [ AskHelp; OfferTrade; Joke; Apologize; Provoke ] do
+            for personality in [ BiasHarness.outgoing; BiasHarness.withdrawn ] do
+                Assert.AreEqual<DialogueResponse>(
+                    Sim.responseFor intent personality,
+                    Occupation.biasResponse (Some Occupation.Fisher) intent personality)
+        // 货郎：仅 SmallTalk 受偏差
+        for intent in [ AskHelp; OfferTrade; Joke; Apologize; Provoke ] do
+            for personality in [ BiasHarness.outgoing; BiasHarness.withdrawn ] do
+                Assert.AreEqual<DialogueResponse>(
+                    Sim.responseFor intent personality,
+                    Occupation.biasResponse (Some Occupation.Peddler) intent personality)
+        // 书生：仅 Joke 受偏差
+        for intent in [ SmallTalk; AskHelp; OfferTrade; Apologize; Provoke ] do
+            for personality in [ BiasHarness.outgoing; BiasHarness.withdrawn ] do
+                Assert.AreEqual<DialogueResponse>(
+                    Sim.responseFor intent personality,
+                    Occupation.biasResponse (Some Occupation.Scholar) intent personality)
+
+    // ---- 确定性：同输入两次调用结果一致 ----
+
+    [<TestMethod>]
+    member _.BiasIsDeterministicForTheSameInputs () =
+        for kind in Occupation.all do
+            for intent in [ SmallTalk; AskHelp; OfferTrade; Joke; Apologize; Provoke ] do
+                for personality in [ BiasHarness.outgoing; BiasHarness.withdrawn; BiasHarness.grumpy ] do
+                    let first = Occupation.biasResponse (Some kind) intent personality
+                    let second = Occupation.biasResponse (Some kind) intent personality
+                    Assert.AreEqual<DialogueResponse>(first, second)
+
+    // ---- 与 chooseDialogueWith 复合：偏差写进 DialogueOutcome/记忆/年鉴 ----
+
+    [<TestMethod>]
+    member _.ChooseDialogueWithIdentityMatchesTheHistoricPath () =
+        let world = Sim.initialWorldN 42UL 4 |> BiasHarness.atNpc 0
+        let npc = world.Npcs.[0]
+        let identityOutcome =
+            match Sim.chooseDialogueWith Sim.responseFor npc.Id AskHelp world with
+            | DialogueSucceeded (outcome, _) -> outcome
+            | DialogueRejected (failure, _) -> Assert.Fail($"rejected: {failure}"); Unchecked.defaultof<DialogueOutcome>
+        Assert.AreEqual<DialogueResponse>(Sim.responseFor AskHelp npc.Mind.Personality, identityOutcome.Response)
+
+    [<TestMethod>]
+    member _.ChooseDialogueWithBiasRecordsTheBiasedResponse () =
+        let world = Sim.initialWorldN 42UL 4 |> BiasHarness.atNpc 0
+        let npc = world.Npcs.[0]
+        let biasedRespond = Occupation.biasResponse (Some Occupation.Farmer)
+        let response, outcomeWorld =
+            match Sim.chooseDialogueWith biasedRespond npc.Id AskHelp world with
+            | DialogueSucceeded (outcome, next) ->
+                Assert.AreEqual<DialogueResponse>(
+                    Occupation.biasResponse (Some Occupation.Farmer) AskHelp npc.Mind.Personality,
+                    outcome.Response)
+                outcome.Response, next
+            | DialogueRejected (failure, _) -> Assert.Fail($"rejected: {failure}"); Unchecked.defaultof<_>, Unchecked.defaultof<World>
+        // 目标村民记忆里记录的是偏差后的回应
+        let remembered =
+            outcomeWorld.Npcs.[0].Mind.Memory
+            |> List.tryPick (fun memory ->
+                match memory.Kind with
+                | Dialogue (_, _, response) -> Some response
+                | _ -> None)
+        Assert.AreEqual<DialogueResponse option>(Some response, remembered)
diff --git a/src/LivingVillage.Kernel/Occupation.fs b/src/LivingVillage.Kernel/Occupation.fs
index 2168c4e..8ce5060 100644
--- a/src/LivingVillage.Kernel/Occupation.fs
+++ b/src/LivingVillage.Kernel/Occupation.fs
@@ -241,3 +241,34 @@ module Occupation =
     /// Sim.quotePrice 的输出经职业偏置映射；None（无报价）原样穿透。
     let biasedQuote (kind: Kind option) (playerIsBuyer: bool) (baseQuote: float32 option) : float32 option =
         baseQuote |> Option.map (fun price -> price * quoteBiasOf kind playerIsBuyer)
+
+    // ---- 对话分支倾向（design §5 / P-d）：村民对玩家职业的确定性回应偏差 ----
+    // 全部为纯函数重映射：基底仍走 Sim.responseFor 的人格口径，偏差不引入随机。
+    // 无职业（None）= 原回应逐字节不变。
+    // 规则（各自只作用于签名意图，其余意图原样穿透）：
+    //   农夫 AskHelp：Refused → Helpful（老实人家，求助不落空）；
+    //   渔夫 SmallTalk：Reserved → Friendly（聊的是天气鱼汛，冷场变热络）；
+    //   货郎 SmallTalk：Reserved → Bargaining（三句不离买卖，更易进讨价还价）；
+    //   书生 Joke：完全覆盖为 Reserved（读过书的人讲笑话，众人反而拘谨）——
+    //   与 personality 相反时采用完全覆盖语义而非概率偏向，确定性可测（design §5 反差感）。
+    let private remapResponse
+        (kind: Kind)
+        (intent: Sim.DialogueIntent)
+        (baseResponse: Sim.DialogueResponse)
+        : Sim.DialogueResponse =
+        match kind, intent, baseResponse with
+        | Farmer, Sim.AskHelp, Sim.Refused -> Sim.Helpful
+        | Fisher, Sim.SmallTalk, Sim.Reserved -> Sim.Friendly
+        | Peddler, Sim.SmallTalk, Sim.Reserved -> Sim.Bargaining
+        | Scholar, Sim.Joke, _ -> Sim.Reserved
+        | _ -> baseResponse
+
+    let biasResponse
+        (kind: Kind option)
+        (intent: Sim.DialogueIntent)
+        (personality: Sim.Personality)
+        : Sim.DialogueResponse =
+        let baseResponse = Sim.responseFor intent personality
+        match kind with
+        | None -> baseResponse
+        | Some kind -> remapResponse kind intent baseResponse
diff --git a/src/LivingVillage.Kernel/Sim.fs b/src/LivingVillage.Kernel/Sim.fs
index 5c4e107..348a60e 100644
--- a/src/LivingVillage.Kernel/Sim.fs
+++ b/src/LivingVillage.Kernel/Sim.fs
@@ -299,7 +299,8 @@ module Sim =
 
     let clamp (v: float32) (lo: float32) (hi: float32) : float32 = if v < lo then lo elif v > hi then hi else v
 
-    let private appendAnnal (entry: AnnalEntry) (world: World) : World =
+    /// P-d 起对调用方公开（剧情线年鉴写入复用同一裁剪口径，语义不变）。
+    let appendAnnal (entry: AnnalEntry) (world: World) : World =
         { world with Annals = (entry :: world.Annals) |> List.truncate maxAnnalEntries }
 
     let hungerDecayPerTick = 0.0012f
@@ -765,7 +766,8 @@ module Sim =
             { Target = target
               Options = dialogueOptions })
 
-    let private responseFor (intent: DialogueIntent) (personality: Personality) : DialogueResponse =
+    /// 纯人格回应函数；P-d 起对调用方公开，供 Occupation.biasResponse 复用原口径。
+    let responseFor (intent: DialogueIntent) (personality: Personality) : DialogueResponse =
         match intent with
         | SmallTalk -> if personality.Extraversion >= 0.5f then Friendly else Reserved
         | AskHelp -> if personality.Honesty >= 0.4f then Helpful else Refused
@@ -782,7 +784,12 @@ module Sim =
         sprintf "rumor tick=%d source=%A narrator=%A receiver=%A depth=%d"
             rumor.Tick rumor.Source rumor.Narrator rumor.Receiver rumor.Depth
 
-    let chooseDialogue (target: NpcId) (intent: DialogueIntent) (world: World) : DialogueResult =
+    let chooseDialogueWith
+        (respond: DialogueIntent -> Personality -> DialogueResponse)
+        (target: NpcId)
+        (intent: DialogueIntent)
+        (world: World)
+        : DialogueResult =
         match findNpcIndex target world.Npcs with
         | None -> DialogueRejected(DialogueTargetNotFound, world)
         | Some targetIndex ->
@@ -794,7 +801,7 @@ module Sim =
             elif not (dialogueAvailable targetNpc) then
                 DialogueRejected(DialogueTargetUnavailable, world)
             else
-                let response = responseFor intent targetNpc.Mind.Personality
+                let response = respond intent targetNpc.Mind.Personality
                 let outcome =
                     { Tick = world.Tick
                       Actor = playerId
@@ -842,6 +849,10 @@ module Sim =
                         withRumorAnnal
                 DialogueSucceeded(outcome, withDialogueAnnal)
 
+    /// 既有入口：无职业偏差的人格回应路径（identity，与历史行为逐字节一致）。
+    let chooseDialogue (target: NpcId) (intent: DialogueIntent) (world: World) : DialogueResult =
+        chooseDialogueWith responseFor target intent world
+
     let annalText (world: World) : string =
         let rows =
             world.Annals