Phase 19 — onboarding: hint tour + Help modal + tooltip pass

Three-agent fan-out (gdscript-refactor x3) ships the chosen Phase 19
approach: contextual hints during first session + a Help reference,
plus a sweep of hover tooltips for desktop discoverability.

- HintSystem (autoload) + HintOverlay (layer 22 top-center banner):
  7-step tour gated on player events — welcome (boot+2s), pawn select,
  build drawer open, stockpile painted, work matrix open, day_ended,
  tour_complete. Per-hint dismissals persist as Array[String] in
  GameState.settings['dismissed_hints']. Max-3 FIFO queue if hints
  chain. Reduce-motion path snaps in/out instead of tweening.
  Reset_tour() public API for the Help modal.

- HelpModal (layer 20): 5-tab static reference (Controls / Verbs /
  Priorities / Storyteller / Tips). Opens via EventBus.help_requested,
  dimmed backdrop, X/Esc/backdrop-tap dismiss. SettingsMenu gains an
  'Onboarding' section: Show-hints checkbox, Help button (emits
  help_requested), Reset hints button (calls HintSystem.reset_tour with
  has_method guard). Pre-existing 'W' keybind reference fixed to 'P'.

- Tooltip pass: tooltip_text via Strings.t on every TopBar button
  (10 buttons incl. speed shortcuts), BuildDrawer FAB, and every tool
  button in BuildDrawer (21 tools). _add_tool_btn extended with optional
  tooltip param. ~34 new tooltip.* string keys.

Contracts pre-written (Opus): EventBus.help_requested, hint_dismissed,
ui_panel_opened signals; GameState show_hints + dismissed_hints
defaults; BuildDrawer.open + WorkPriorityMatrix.open emit
ui_panel_opened so HintSystem can subscribe via one signal.

Also recorded [MED] known bug in memory.md: drag-paint with active
paint tool is eaten by camera drag-pan.

MCP runtime verified: welcome banner fires 2s after boot, dismiss
queues build_drawer hint on next ui_panel_opened, dismissed_hints
persisted as ['welcome'], HelpModal opens via help_requested with
tab switching working (Controls → Tips verified visually).

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

scenes/ui/top_bar.gd

@@ -54,6 +54,14 @@ func _ready() -> void:
 	ultra_btn.text   = Strings.t(&"speed.ultra")
 	save_btn.text    = Strings.t(&"ui.save")
 	load_btn.text    = Strings.t(&"ui.load")
+
+	# Phase 19 — desktop hover tooltips (no-op on touch).
+	pause_btn.tooltip_text  = Strings.t(&"tooltip.pause")
+	normal_btn.tooltip_text = Strings.t(&"tooltip.speed_normal")
+	fast_btn.tooltip_text   = Strings.t(&"tooltip.speed_fast")
+	ultra_btn.tooltip_text  = Strings.t(&"tooltip.speed_ultra")
+	save_btn.tooltip_text   = Strings.t(&"tooltip.save")
+	load_btn.tooltip_text   = Strings.t(&"tooltip.load")
 	tick_label.text   = "(boot)"
 	clock_label.text  = Strings.t(&"clock.format").format({"d": 1, "t": "06:00"})
 	season_label.text = Strings.t(&"season.format").format({"s": Strings.t(&"season.spring"), "d": 1})
@@ -159,6 +167,7 @@ func _add_build_btn() -> void:
 	build_btn.text = "🔨"
 	build_btn.custom_minimum_size = Vector2(40, 40)
 	build_btn.focus_mode = Control.FOCUS_NONE
+	build_btn.tooltip_text = Strings.t(&"tooltip.build")
 	build_btn.pressed.connect(_on_build_pressed)
 	button_row.add_child(build_btn)
 	Audit.log("top_bar", "Build button added to ButtonRow")
@@ -183,6 +192,7 @@ func _add_settings_btn() -> void:
 	settings_btn.text = "⚙"
 	settings_btn.custom_minimum_size = Vector2(40, 40)
 	settings_btn.focus_mode = Control.FOCUS_NONE
+	settings_btn.tooltip_text = Strings.t(&"tooltip.settings")
 	settings_btn.pressed.connect(_on_settings_pressed)
 	button_row.add_child(settings_btn)
 	Audit.log("top_bar", "Settings button added to ButtonRow")
@@ -208,6 +218,7 @@ func _add_work_log_btns() -> void:
 	work_btn.text = "👷"
 	work_btn.custom_minimum_size = Vector2(40, 40)
 	work_btn.focus_mode = Control.FOCUS_NONE
+	work_btn.tooltip_text = Strings.t(&"tooltip.work")
 	work_btn.pressed.connect(_on_work_pressed)
 	button_row.add_child(work_btn)
 
@@ -216,6 +227,7 @@ func _add_work_log_btns() -> void:
 	_log_btn.text = "🔔"
 	_log_btn.custom_minimum_size = Vector2(40, 40)
 	_log_btn.focus_mode = Control.FOCUS_NONE
+	_log_btn.tooltip_text = Strings.t(&"tooltip.log")
 	_log_btn.pressed.connect(_on_log_pressed)
 	button_row.add_child(_log_btn)