Phase 17/18 closure: stockpile filter UI + day summary + atmospheric audio

Three-agent fan-out (gdscript-refactor x3) closing deferred polish:

- Stockpile chip filter UI: new StockpilePanel (layer 18, right-anchored,
  mirrors WorkbenchPanel). 5-priority segmented control + 21-chip 4-col
  filter grid using Item.ALL_TYPES; wildcard (empty accepted_types) shows
  all chips checked with 'All' hint, first explicit pick switches to
  explicit-list mode. Selection chain extended to pawn → workbench →
  stockpile with mutual exclusion. 12 ui.stockpile.* + 13 item.* keys.

- DaySummaryCard: layer-19 modal auto-opens at dusk→night via day_ended,
  auto-pauses sim, shows day+season header, weather row, stats grid with
  green/yellow/red tension bar, Continue dismiss + backdrop tap.
  Settings 'Show end-of-day summary' toggle persists via GameState.

- Atmospheric audio: rain ambient loop (Cozy Melodies Pack 6) on
  weather_changed rain/storm with 0.5s fade-out on clear; thunder sting
  (Magic and Spells 6) on rain→storm transition; raid warning sting
  (Sword Pack 1, 'blades drawn') on EventBus.wolf_spawned. All on SFX
  bus — inherits existing slider + suspend mute.

Contracts pre-written before fan-out: EventBus.stockpile_selected /
stockpile_deselected / wolf_spawned signals; WolfSpawner._trigger_raid
+ _on_request_wolf_spawn now emit wolf_spawned with the spawned array.

MCP runtime verified: StockpilePanel opens with 21 chips, DaySummaryCard
renders weather row + tension bar + auto-pause, rain_player.playing=true
on weather_changed(rain), all three new SFX keys in Audio.SFX_FILES.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scenes/world/selection.gd

@@ -17,6 +17,8 @@ var _selected_pawn: Pawn = null
 ## Currently selected workbench, or null.  Mutually exclusive with _selected_pawn —
 ## selecting one clears the other (see _select / _select_workbench).
 var _selected_workbench: Workbench = null
+## Currently selected stockpile zone, or null.  Mutually exclusive with the above.
+var _selected_stockpile = null  # StockpileZone (duck-typed to avoid circular preload)
 var _camera = null  # Camera2D (CameraRig) — set via bind_camera(); duck-typed to avoid circular preload
 
 # When Designation paint mode is active this flag is raised by Designation so
@@ -76,12 +78,17 @@ func _unhandled_input(event: InputEvent) -> void:
 			get_viewport().set_input_as_handled()
 			Audit.log("selection", "escape: deselected workbench")
 			return
+		if _selected_stockpile != null:
+			_deselect_stockpile()
+			get_viewport().set_input_as_handled()
+			Audit.log("selection", "escape: deselected stockpile")
+			return
 
 	# ── Mouse: only handle button events below ───────────────────────────────────
 	if not (event is InputEventMouseButton):
 		return
 
-	# ── Right-click: cancel designation (if active) or deselect pawn / workbench ──
+	# ── Right-click: cancel designation (if active) or deselect pawn / workbench / stockpile ──
 	if event.button_index == MOUSE_BUTTON_RIGHT and event.pressed:
 		# Designation cancellation is handled by Designation._input; if we see
 		# this right-click, no designation was active.  Deselect whatever is selected.
@@ -91,6 +98,9 @@ func _unhandled_input(event: InputEvent) -> void:
 		elif _selected_workbench != null:
 			_deselect_workbench()
 			get_viewport().set_input_as_handled()
+		elif _selected_stockpile != null:
+			_deselect_stockpile()
+			get_viewport().set_input_as_handled()
 		return
 
 	if event.button_index != MOUSE_BUTTON_LEFT:
@@ -139,10 +149,18 @@ func _handle_click(screen_pos: Vector2) -> void:
 		_select_workbench(hit_workbench)
 		return
 
-	# Empty tile with no current pawn selection → also clear any workbench selection.
+	# Click on a stockpile zone → open the filter editor panel.
+	var hit_stockpile = World.stockpile_at_tile(tile)
+	if hit_stockpile != null:
+		_select_stockpile(hit_stockpile)
+		return
+
+	# Empty tile with no current pawn selection → also clear any workbench / stockpile selection.
 	if _selected_pawn == null:
 		if _selected_workbench != null:
 			_deselect_workbench()
+		if _selected_stockpile != null:
+			_deselect_stockpile()
 		return
 
 	# Empty walkable tile with a selection → queue a forced job. Decision picks
@@ -161,9 +179,11 @@ func _handle_click(screen_pos: Vector2) -> void:
 func _select(pawn: Pawn) -> void:
 	if _selected_pawn == pawn:
 		return
-	# Mutual exclusion with workbench selection: clear it before promoting pawn.
+	# Mutual exclusion with workbench and stockpile: clear them before promoting pawn.
 	if _selected_workbench != null:
 		_deselect_workbench()
+	if _selected_stockpile != null:
+		_deselect_stockpile()
 	if _selected_pawn != null:
 		_selected_pawn.set_selected(false)
 		EventBus.pawn_deselected.emit()
@@ -184,12 +204,14 @@ func _deselect() -> void:
 
 
 ## Select a workbench → opens the bill-editor panel via EventBus.
-## Mutually exclusive with pawn selection: clears _selected_pawn first.
+## Mutually exclusive with pawn and stockpile selections.
 func _select_workbench(wb) -> void:
 	if _selected_workbench == wb:
 		return
 	if _selected_pawn != null:
 		_deselect()
+	if _selected_stockpile != null:
+		_deselect_stockpile()
 	if _selected_workbench != null:
 		EventBus.workbench_deselected.emit()
 	_selected_workbench = wb
@@ -205,6 +227,30 @@ func _deselect_workbench() -> void:
 	EventBus.workbench_deselected.emit()
 
 
+## Select a stockpile zone → opens the filter editor panel via EventBus.
+## Mutually exclusive with pawn and workbench selections.
+func _select_stockpile(zone) -> void:
+	if _selected_stockpile == zone:
+		return
+	if _selected_pawn != null:
+		_deselect()
+	if _selected_workbench != null:
+		_deselect_workbench()
+	if _selected_stockpile != null:
+		EventBus.stockpile_deselected.emit()
+	_selected_stockpile = zone
+	EventBus.stockpile_selected.emit(zone)
+	Audit.log("selection", "selected stockpile at %s" % str(zone.position))
+
+
+func _deselect_stockpile() -> void:
+	if _selected_stockpile == null:
+		return
+	Audit.log("selection", "deselected stockpile")
+	_selected_stockpile = null
+	EventBus.stockpile_deselected.emit()
+
+
 ## Cycle the selection forward (dir=1) or backward (dir=-1) through World.pawns.
 ## Wraps around.  If no pawn currently selected, picks World.pawns[0].
 ## Pans the camera to the newly selected pawn's tile.