fix(client): address PR #43 review — walk key mismatch + 5 suggestions

Fix SOUND_EVENT_ASSETS walk-speed keys to match actual filename
(sfx_footstep_metal_walk), add play_loop null guard, source indicator
colors from Constants, extract CAMERA_DEFAULT_ZOOM, document
consume-once semantics on close_sound_events.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

client/scripts/autoloads/audio_manager.gd

@@ -142,6 +142,8 @@ func play_loop(asset_key: String, bus: String = BUS_AMBIENT) -> AudioStreamPlaye
 		return null
 	stop_loop(asset_key)
 	var loop_stream := stream.duplicate() as AudioStream
+	if loop_stream == null:
+		return null
 	_enable_loop(loop_stream)
 	var player := AudioStreamPlayer.new()
 	player.stream = loop_stream
@@ -175,10 +177,10 @@ func stop_all_loops() -> void:
 # No asset for Voice events in v0.1 — play_sound_event no-ops gracefully
 # (D-038: "renders as audio if asset exists, or visual indicator + monologue if not").
 const SOUND_EVENT_ASSETS: Dictionary = {
-	"Footstep":       "sfx_footstep_metal",
-	"FootstepWalk":   "sfx_footstep_metal",
-	"FootstepCareful":"sfx_footstep_metal",
-	"FootstepCrouch": "sfx_footstep_metal",
+	"Footstep":       "sfx_footstep_metal_walk",
+	"FootstepWalk":   "sfx_footstep_metal_walk",
+	"FootstepCareful":"sfx_footstep_metal_walk",  # D-053: same asset until stance-differentiated audio lands
+	"FootstepCrouch": "sfx_footstep_metal_walk",  # D-053: same asset until stance-differentiated audio lands
 	"FootstepSprint": "sfx_footstep_metal_run",
 	"FootstepRun":    "sfx_footstep_metal_run",
 }

client/scripts/constants.gd

@@ -96,6 +96,9 @@ const FACING_INDICATOR_OFFSET: float = 14.0
 # two columns of text comfortably, leaves world game visible alongside.
 const DIALOGUE_MAX_WIDTH: int = 640
 
+# Default camera zoom — used as fallback when get_camera_2d() returns null
+const CAMERA_DEFAULT_ZOOM: Vector2 = Vector2(2.0, 2.0)
+
 # #517: Implant UI font color grading — avoid pure white, project through a lens
 const IMPLANT_TEXT_COLOR: Color = Color("#E0F7FA")   # Cyan-white — primary text
 const IMPLANT_TEXT_DIM: Color = Color("#9EBFC4")     # Dimmed variant — secondary text

client/scripts/main.gd

@@ -201,6 +201,8 @@ func _process(_delta: float) -> void:
 # D-018 #125: Play close-range sound events — fired once per snapshot tick.
 # Each event is passed to AudioManager.play_sound_event() for 2D positional playback
 # on the WorldSFX bus. Events with no registered asset are silently skipped (D-038).
+# Consume-once: events are cleared after processing so they don't replay if
+# _process runs again before the next server tick (D-009 multiplayer-safe pattern).
 func _play_close_sound_events() -> void:
 	for evt in GameState.close_sound_events:
 		if not evt is Dictionary or not evt.has("x") or not evt.has("y"):

client/scripts/rendering/sound_indicator_renderer.gd

@@ -26,10 +26,10 @@ const EDGE_INSET: float = 20.0          # Pixels inward from viewport edge
 const ARROW_HALF: float = 7.0           # Half-width of arrowhead base
 const ARROW_LEN: float = 12.0           # Length from tip to base
 
-# D-018/D-069 colors
-const COLOR_NEUTRAL: Color = Color("#c8d0e0")  # Generic / footstep
-const COLOR_VOICE: Color = Color("#e8c547")     # Speech / conversation
-const COLOR_DANGER: Color = Color("#d45d5d")    # Alert / threat / gunshot
+# D-018/D-069 colors — sourced from Constants to prevent palette drift
+const COLOR_NEUTRAL: Color = Constants.INSERT_COLOR_TEXT   # Generic / footstep
+const COLOR_VOICE: Color = Constants.ENTITY_COLOR_POI      # Speech / conversation
+const COLOR_DANGER: Color = Constants.ENTITY_COLOR_HOSTILE  # Alert / threat / gunshot
 
 # Indicators: [{x, y, event_type, elapsed}]
 var _indicators: Array = []
@@ -89,7 +89,7 @@ func _draw() -> void:
 	# the fog edge and don't clip to the physical screen border.
 	var vp_size := get_viewport().get_visible_rect().size
 	var cam := get_viewport().get_camera_2d()
-	var zoom := cam.zoom if cam else Vector2(2.0, 2.0)
+	var zoom := cam.zoom if cam else Constants.CAMERA_DEFAULT_ZOOM
 	var half_extents: Vector2 = vp_size / (2.0 * zoom)
 
 	for ind in _indicators:

client/tests/test_audio_bus_routing.gd

@@ -272,9 +272,9 @@ func test_audio_manager_sound_event_assets_registry_exists() -> void:
 	assert_that(AudioManager.SOUND_EVENT_ASSETS.size()).is_greater(0)
 
 func test_audio_manager_footstep_maps_to_sfx_footstep_metal() -> void:
-	## #125: "Footstep" event type → sfx_footstep_metal (D-038 asset).
+	## #125: "Footstep" event type → sfx_footstep_metal_walk (D-038 asset).
 	assert_that(AudioManager.SOUND_EVENT_ASSETS.has("Footstep")).is_true()
-	assert_that(AudioManager.SOUND_EVENT_ASSETS["Footstep"]).is_equal("sfx_footstep_metal")
+	assert_that(AudioManager.SOUND_EVENT_ASSETS["Footstep"]).is_equal("sfx_footstep_metal_walk")
 
 func test_audio_manager_footstep_sprint_maps_to_sfx_footstep_metal_run() -> void:
 	## #125: "FootstepSprint" → sfx_footstep_metal_run (D-038 faster footstep).