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>

autoload/game_state.gd

@@ -17,6 +17,7 @@ var settings: Dictionary = {
 	"pause_on_wanderer":  true,
 	"pause_on_pawn_down": true,
 	"pause_on_modal":     true,
+	"show_day_summary":   true,
 	"audio_master":       1.0,
 	"audio_music":        1.0,
 	"audio_sfx":          1.0,