feat(desktop): P15 开局职业选择页——新档四选一+暂不选择，接入 v3 存档与当日任务

- MenuState：新增 OccupationSelect 页与 StartNewGameWith 命令；occupationOptions=农夫/渔夫/货郎/书生/暂不选择，
  默认高亮「暂不选择」= 不写职业的旧行为；四选一确认后发 StartNewGameWith，ESC 返回主菜单（既有 MainMenu
  行为与测试不变）。
- WorldBootstrap.occupationStateFor/refreshOccupationToday：按 seed+职业种子生成/跨日刷新当日 Offered 任务。
- Game：主菜单「开始新游戏」→ 职业选择页；选定后 initialWorldWithOccupation 注入 Money/Energy 与 Today，
  m5View.Task 随之写入 v3 存档；游玩中按日刷新；autoplay/flow 默认走「暂不选择」保持旧演示行为；DrawMenu 渲染职业页。
- 测试 Desktop 93（新增 6）：职业页选项顺序/默认 None/标签、确认命令与返回、bootstrap 四职业 Money/Energy+当日池内
  Offered 任务、四职业 v3 round-trip（职业+任务逐字段）、T 面板显示所选职业的模板名与「待接受」、跨日刷新保持同日。

1 files changed, 29 insertions, 0 deletions

diff --git a/src/LivingVillage.Desktop/MenuState.fs b/src/LivingVillage.Desktop/MenuState.fs
index 2848e22..619ac58 100644
--- a/src/LivingVillage.Desktop/MenuState.fs
+++ b/src/LivingVillage.Desktop/MenuState.fs
@@ -4,6 +4,7 @@ open LivingVillage.Kernel
 
 type MenuPage =
     | MainMenu
+    | OccupationSelect
     | Settings
     | Controls
     | Playing
@@ -33,6 +34,7 @@ type MenuCommand =
     | NoCommand
     | ContinueGame
     | StartNewGame
+    | StartNewGameWith of Occupation.Kind option
     | LoadGame
     | ApplySettings of SimulationControl
     | ExitGame
@@ -100,9 +102,26 @@ module MenuState =
         | ControlsItem -> "操作说明"
         | ExitItem -> "退出"
 
+    /// 开局四选一 + 「暂不选择」（None = 旧行为，无职业）。
+    let occupationOptions : Occupation.Kind option list =
+        [ Some Occupation.Farmer
+          Some Occupation.Fisher
+          Some Occupation.Peddler
+          Some Occupation.Scholar
+          None ]
+
+    let occupationLabel (occupation: Occupation.Kind option) : string =
+        match occupation with
+        | Some kind -> Occupation.nameOf kind
+        | None -> "暂不选择"
+
+    let selectedOccupation (state: MenuState) : Occupation.Kind option =
+        occupationOptions |> List.item state.Selected
+
     let private optionsFor (state: MenuState) : int =
         match state.Page with
         | MainMenu -> items state |> List.length
+        | OccupationSelect -> occupationOptions.Length
         | Settings -> settings.Length
         | _ -> 0
 
@@ -150,6 +169,14 @@ module MenuState =
     let openSettings (state: MenuState) : MenuState =
         { state with Page = Settings; Selected = 0; ReturnPage = state.Page; Error = None }
 
+    /// 新档确认后进入职业选择页；默认选中「暂不选择」= 不写职业的旧行为。
+    let openOccupationSelect (state: MenuState) : MenuState =
+        { state with
+            Page = OccupationSelect
+            Selected = occupationOptions.Length - 1
+            ReturnPage = state.Page
+            Error = None }
+
     let openControls (state: MenuState) : MenuState =
         { state with Page = Controls; Selected = 0; ReturnPage = state.Page; Error = None }
 
@@ -187,6 +214,7 @@ module MenuState =
         | Back ->
             match state.Page with
             | MainMenu -> state, ExitGame
+            | OccupationSelect -> openMain state, NoCommand
             | Settings
             | Controls -> returnFromSubpage state, NoCommand
             | LoadError -> openMain state, NoCommand
@@ -194,6 +222,7 @@ module MenuState =
         | Confirm ->
             match state.Page with
             | MainMenu -> confirmMain state
+            | OccupationSelect -> state, StartNewGameWith (selectedOccupation state)
             | Settings ->
                 let nextSettings = selectedControl state
                 { state with Settings = nextSettings }, ApplySettings nextSettings