Add accessibility pass: escalation meter and working HUD font scale

- Escalation cue now includes a shape meter and numeric level
  ("Escalation: Blocking [###--] L3/5") in addition to the colour and name, so it
  reads in grayscale. Hud.escalation_meter(level) is pure and tested.
- HUD font scale from settings actually works: set_font_scale() resizes fonts via
  theme overrides instead of Control.scale, which pushed the right-anchored clock
  label off-screen. It now covers the top, log, target, hint, time, mode,
  escalation, cooldown, and debug labels.
- Settings load before the HUD exists, so _ready() re-applies player settings after
  _build_ui(); previously a saved font scale was ignored until the next apply.

Tests/docs
- Headless suite 134 -> 139 (test_accessibility.gd).
- Verified visually at 1.4x scale: no overflow, meter readable.
- README, TODO section moved to DONE, MEMORY. Version 0.2.9.

src/game/game_manager.gd

@@ -141,6 +141,9 @@ func _ready() -> void:
 	_connect_crowd()
 
 	_build_ui()
+	# The HUD does not exist yet when settings are loaded, so push them again now
+	# that it does (otherwise the saved font scale is ignored until the next apply).
+	_apply_settings(player_settings)
 	_last_phase = -1
 	_apply_phase_lighting()
 	# Boot into the venue menu; the shift starts when the player picks a venue.