docs(0.S): the doc fences migrated by ludic migrate state; LANGUAGE.md's state section says what the tool and the checker do now; no module-level var left in the docs

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/language/structure/kw-enum.md

@@ -40,18 +40,20 @@ A tagged `match` must be **exhaustive**: it either handles every variant or ends
 program BattleMenu {
   enum Action { Attack, Guard, Item, Flee }
 
-  var current_action: int = Action.Attack
-
-  handler ChooseAction phase Input {
-    let pressed = Input.key()
-    if pressed == 'a' { current_action = Action.Attack }
-    if pressed == 'g' { current_action = Action.Guard }
-    if pressed == 'f' { current_action = Action.Flee }
+  state BattleMenuState {
+    current_action: int = Action.Attack
   }
 
-  handler DrawWorld phase Render {
+  handler ChooseAction(battle_menu_st: mut BattleMenuState) phase Input {
+    let pressed = Input.key()
+    if pressed == 'a' { battle_menu_st.current_action = Action.Attack }
+    if pressed == 'g' { battle_menu_st.current_action = Action.Guard }
+    if pressed == 'f' { battle_menu_st.current_action = Action.Flee }
+  }
+
+  handler DrawWorld(battle_menu_st: BattleMenuState) phase Render {
     Screen.clear(Color.MidnightBlue)
-    match current_action {
+    match battle_menu_st.current_action {
       Action.Attack => Screen.draw_text(x: 8, y: 8, text: "ATTACK", color: Color.Crimson, scale: 2)
       Action.Guard  => Screen.draw_text(x: 8, y: 8, text: "GUARD", color: Color.White, scale: 2)
       _             => Screen.draw_text(x: 8, y: 8, text: "FLEE", color: Color.Gold, scale: 2)

docs/language/structure/kw-program.md

@@ -16,7 +16,7 @@ program SpaceDrift {
   property Position { column: int = 0, row: int = 0 }
   model Player { Position }
 
-  var score: int = 0
+  let score: int = 0
 
   handler Boot phase Start {
     spawn Hero { Position { column: 10, row: 8 } }

docs/language/structure/kw-ui.md

@@ -9,22 +9,24 @@ tip: Declare a retained widget tree as data; the engine lays it out and draws it
 order: 50
 ---
 
-A <code>ui</code> block declares a <b>retained</b> widget tree as data — panels, labels and buttons — and hands layout, drawing and keyboard focus to the engine, so you describe the interface once instead of repainting it every frame. Widget types are `panel` (a container with optional skin/background/border), `col`/`row` (pure stacks), `label`, `button` (focusable), `image` and `spacer`, and their props are evaluated at build time, so `font: title_font` reads a value the program set first. Each `id: Name` mints a `UI_Name` handle you drive from handlers: call `Ui.build()` then `Ui.open(UI_MainMenu)` at start, `Ui.tick(Input.key())` each update to move focus and activate, and `Ui.clicked(UI_Name)` to react. Draw it during `Render` with `Ui.render()` between `Screen.clear` and `Screen.show()`.
+A <code>ui</code> block declares a <b>retained</b> widget tree as data — panels, labels and buttons — and hands layout, drawing and keyboard focus to the engine, so you describe the interface once instead of repainting it every frame. Widget types are `panel` (a container with optional skin/background/border), `col`/`row` (pure stacks), `label`, `button` (focusable), `image` and `spacer`, and their props are evaluated at build time, so `font: TitleScreenState.title_font` reads a value the program set first (a `ui` block names a state's one instance by the state's name). Each `id: Name` mints a `UI_Name` handle you drive from handlers: call `Ui.build()` then `Ui.open(UI_MainMenu)` at start, `Ui.tick(Input.key())` each update to move focus and activate, and `Ui.clicked(UI_Name)` to react. Draw it during `Render` with `Ui.render()` between `Screen.clear` and `Screen.show()`.
 
 ```ludic
 program TitleScreen {
-  var title_font: int = 0
+  state TitleScreenState {
+    title_font: int = 0
+  }
 
   ui MainMenu {
     panel id: Root w: 288 pad: 16 gap: 6 bg: 0x1a1a2c align: center {
-      label  text: "CHRONO RIFT" font: title_font size: 26 fg: 0xffe060 align: center
-      button id: NewGame text: "New Game" font: title_font size: 16 w: 236
-      button id: Quit    text: "Quit"     font: title_font size: 16 w: 236
+      label  text: "CHRONO RIFT" font: TitleScreenState.title_font size: 26 fg: 0xffe060 align: center
+      button id: NewGame text: "New Game" font: TitleScreenState.title_font size: 16 w: 236
+      button id: Quit    text: "Quit"     font: TitleScreenState.title_font size: 16 w: 236
     }
   }
 
-  handler Boot phase Start {
-    title_font = Font.load("/System/Library/Fonts/Supplemental/Arial.ttf")
+  handler Boot(title_screen_st: mut TitleScreenState) phase Start {
+    title_screen_st.title_font = Font.load("/System/Library/Fonts/Supplemental/Arial.ttf")
     Ui.build()
     Ui.open(UI_MainMenu)
   }

docs/language/structure/kw-var.md

@@ -13,18 +13,20 @@ A <code>var</code> declares a <b>mutable</b> binding: unlike `let`, you may reas
 
 ```ludic
 program Scorekeeper {
-  var score: int = 0
-  var elapsed_frames: int = 0
-
-  handler Tick phase Update {
-    elapsed_frames = elapsed_frames + 1
-    if elapsed_frames % 60 == 0 { score = score + 1 }
+  state ScorekeeperState {
+    score: int = 0
+    elapsed_frames: int = 0
   }
 
-  handler DrawWorld phase Render {
+  handler Tick(scorekeeper_st: mut ScorekeeperState) phase Update {
+    scorekeeper_st.elapsed_frames = scorekeeper_st.elapsed_frames + 1
+    if scorekeeper_st.elapsed_frames % 60 == 0 { scorekeeper_st.score = scorekeeper_st.score + 1 }
+  }
+
+  handler DrawWorld(scorekeeper_st: ScorekeeperState) phase Render {
     Screen.clear(Color.MidnightBlue)
     Screen.draw_text(x: 6, y: 4, text: "SCORE", color: Color.White, scale: 1)
-    Screen.draw_number(x: 52, y: 4, value: score, color: Color.Gold, scale: 1)
+    Screen.draw_number(x: 52, y: 4, value: scorekeeper_st.score, color: Color.Gold, scale: 1)
     Screen.show()
   }
 }