feat: add bulk disembark for transport units

- Add disembark action to transport unit action menu when carrying units
- Highlight valid landing tiles adjacent to boats (clear of enemies)
- Unload all passengers onto a single chosen tile at once
- Implement targeting mode with cancel support (Escape or clicking away)
- Extract unitsOnBoat and disembarkTiles logic functions
- Add green diamond tile highlights in view layer

src/games/civilization/CivilizationGame.js

@@ -70,6 +70,7 @@ export default class CivilizationGame extends Phaser.Scene {
     this.logScrollY = 0;
     this.statusQueue = [];
     this.pendingCityAttacks = [];
+    this.disembarkPending = null;
   }
 
   create() {
@@ -104,6 +105,7 @@ export default class CivilizationGame extends Phaser.Scene {
   }
 
   onEscape() {
+    if (this.disembarkPending) { this.cancelDisembark(); return; }
     if (this.modalOpen) return; // modals close themselves
     if (this.phase === 'playing') this.openMenu();
     else this.scene.start('GameMenu');
@@ -671,6 +673,7 @@ export default class CivilizationGame extends Phaser.Scene {
   }
 
   onTileClick(c, r) {
+    if (this.disembarkPending) { this.resolveDisembarkClick(c, r); return; }
     const state = this.state;
     const human = state.humanIndex;
     const city = Logic.cityAt(state, c, r);
@@ -807,6 +810,7 @@ export default class CivilizationGame extends Phaser.Scene {
   }
 
   selectUnit(unit) {
+    this.cancelDisembark();
     this.selectedUnitId = unit?.id ?? null;
     this.view.selectedUnitId = this.selectedUnitId;
     this.view.showPath(null);
@@ -1030,6 +1034,7 @@ export default class CivilizationGame extends Phaser.Scene {
 
   onUnitClick(unit) {
     if (this.modalOpen || this.busy || this.state.current !== this.state.humanIndex) return;
+    this.cancelDisembark();
     this.openUnitActionMenu(unit);
   }
 
@@ -1064,10 +1069,52 @@ export default class CivilizationGame extends Phaser.Scene {
     if (Logic.canEstablishRoute(rules, state, unit)) {
       actions.push({ label: 'Establish Trade Route', onSelect: () => this.tryCaravan(unit) });
     }
+    if (Logic.unitsOnBoat(state, unit).length) {
+      const tiles = Logic.disembarkTiles(rules, state, unit);
+      if (tiles.length) {
+        actions.push({ label: 'Disembark', onSelect: () => this.beginDisembark(unit, tiles) });
+      }
+    }
     actions.push({ label: 'Skip Turn', onSelect: () => { unit.mp = 0; this.selectNextUnit(); } });
     return actions;
   }
 
+  // "Disembark" arms target-picking mode: the next tile click either unloads
+  // the whole hold there (if it's one of the highlighted candidate tiles) or
+  // just cancels, same as clicking away from any other targeting cursor.
+  beginDisembark(boat, tiles) {
+    this.disembarkPending = { boatId: boat.id, tiles };
+    this.view.showDisembarkTiles(tiles);
+  }
+
+  cancelDisembark() {
+    if (!this.disembarkPending) return;
+    this.disembarkPending = null;
+    this.view?.showDisembarkTiles(null);
+  }
+
+  resolveDisembarkClick(c, r) {
+    const { boatId, tiles } = this.disembarkPending;
+    this.cancelDisembark();
+    const match = tiles.find((t) => t.x === c && t.y === r);
+    if (!match) return;
+    const boat = Logic.unitById(this.state, boatId);
+    if (!boat) return;
+    this.tryDisembarkAll(boat, match.dx, match.dy);
+  }
+
+  // disembarkTiles() only ever offers tiles clear of foreign cities/units, so
+  // every passenger's individual disembark() below is guaranteed to succeed —
+  // no war-confirmation branch needed here (contrast tryStep's single-unit
+  // path, which can walk a unit into a tile that does need one).
+  tryDisembarkAll(boat, dx, dy) {
+    if (this.state.current !== this.state.humanIndex) return;
+    for (const u of Logic.unitsOnBoat(this.state, boat)) {
+      Logic.disembark(this.rules, this.state, u, dx, dy);
+    }
+    this.afterAction();
+  }
+
   openUnitActionMenu(unit) {
     const def = this.rules.units[unit.type];
     this.openActionListMenu(def.name, this.getUnitActions(unit));
@@ -1191,6 +1238,7 @@ export default class CivilizationGame extends Phaser.Scene {
   onEndTurn() {
     if (this.busy || this.modalOpen || this.phase !== 'playing') return;
     if (this.state.current !== this.state.humanIndex) return;
+    this.cancelDisembark();
     Logic.endCivTurn(this.rules, this.state, this.state.humanIndex);
     this.saveGame();
     this.runToHumanTurn();

src/games/civilization/CivilizationLogic.js

@@ -810,8 +810,12 @@ function spendMove(unit, cost) {
   unit.moved = true;
 }
 
+export function unitsOnBoat(state, boat) {
+  return state.units.filter((u) => u.carriedBy === boat.id);
+}
+
 function cargoCount(state, boat) {
-  return state.units.filter((u) => u.carriedBy === boat.id).length;
+  return unitsOnBoat(state, boat).length;
 }
 
 function dropCarried(rules, state, unit, x, y) {
@@ -836,6 +840,29 @@ export function disembark(rules, state, unit, dx, dy) {
   return out;
 }
 
+const ADJACENT_DIRS = [[1, 0], [-1, 0], [0, 1], [0, -1], [1, 1], [1, -1], [-1, 1], [-1, -1]];
+
+// Land tiles next to `boat` that are clear of any foreign city/units — used
+// to offer the human player a "Disembark" action (see CivilizationGame.js)
+// that unloads the whole hold onto a single chosen tile at once. Kept clear
+// of enemies so it never surprises the player with a fight; attacking off a
+// transport is still possible unit-by-unit via the AI's own logic, just not
+// through this bulk convenience command.
+export function disembarkTiles(rules, state, boat) {
+  const tiles = [];
+  for (const [dx, dy] of ADJACENT_DIRS) {
+    const x = boat.x + dx;
+    const y = boat.y + dy;
+    if (!inBounds(state.world, x, y)) continue;
+    if (terrainAt(rules, state.world, x, y).water) continue;
+    const city = cityAt(state, x, y);
+    if (city && city.civ !== boat.civ) continue;
+    if (unitsAt(state, x, y).some((u) => u.civ !== boat.civ)) continue;
+    tiles.push({ x, y, dx, dy });
+  }
+  return tiles;
+}
+
 function resolveHut(rules, state, unit) {
   const civ = state.civs[unit.civ];
   const roll = rand(state);

src/games/civilization/CivilizationMapView.js

@@ -74,10 +74,11 @@ export class CivilizationMapView {
       }
     }
     this.pathGfx = scene.add.graphics();
+    this.disembarkGfx = scene.add.graphics();
     this.dynamic = scene.add.container(0, 0);
     this.root.add([
       ...this.terrainChunks.map((c) => c.rt),
-      this.pathGfx, this.dynamic,
+      this.pathGfx, this.disembarkGfx, this.dynamic,
       ...this.fogChunks.map((c) => c.rt),
     ]);
 
@@ -968,6 +969,30 @@ export class CivilizationMapView {
     }
   }
 
+  // Highlights candidate landing tiles while a "Disembark" action is armed
+  // (see CivilizationGame.js) — pass null/empty to clear. Diamond shape
+  // mirrors paintProceduralTile's tile stamp so the outline sits flush with
+  // the tile underneath it.
+  showDisembarkTiles(tiles) {
+    this.disembarkGfx.clear();
+    if (!tiles || !tiles.length) return;
+    const cy = TILE_H / 2;
+    this.disembarkGfx.lineStyle(3, 0x4a9e44, 0.95);
+    this.disembarkGfx.fillStyle(0x4a9e44, 0.22);
+    for (const { x: c, y: r } of tiles) {
+      const x = this.isoX(c, r);
+      const y = this.isoY(c, r);
+      this.disembarkGfx.beginPath();
+      this.disembarkGfx.moveTo(x, y + cy - TILE_H / 2);
+      this.disembarkGfx.lineTo(x + TILE_W / 2, y + cy);
+      this.disembarkGfx.lineTo(x, y + cy + TILE_H / 2);
+      this.disembarkGfx.lineTo(x - TILE_W / 2, y + cy);
+      this.disembarkGfx.closePath();
+      this.disembarkGfx.fillPath();
+      this.disembarkGfx.strokePath();
+    }
+  }
+
   // -------------------------------------------------------------------------
   // Minimap