Build stamp via assets/build_info.json (reliable: same path as the catalog)

config/version didn't survive export cleanly. Instead checkpoint_ops writes
assets/build_info.json at build time (a plain JSON file, packed by the same
include_filter as the avatar catalog) and the menu + in-world HUD read it
with FileAccess. Shows 'build PC3 <commit>' so playtest reports say exactly
which build is running.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015jtxAiu5dAW4WxCNdGkrkJ

scripts/main_menu.gd

@@ -49,9 +49,20 @@ var _is_authenticating: bool = false
 
 # ─── Lifecycle ────────────────────────────────────────────────────────────────
 
+
+static func _build_label() -> String:
+	var f := FileAccess.open("res://assets/build_info.json", FileAccess.READ)
+	if f == null:
+		return "dev"
+	var d = JSON.parse_string(f.get_as_text())
+	if d is Dictionary:
+		return "%s %s" % [d.get("checkpoint", "?"), d.get("commit", "?")]
+	return "dev"
+
+
 func _ready() -> void:
 	var v := Label.new()
-	v.text = "build %s" % ProjectSettings.get_setting("application/config/version", "dev")
+	v.text = "build %s" % _build_label()
 	v.add_theme_color_override("font_color", Color(1, 1, 1, 0.4))
 	v.add_theme_font_size_override("font_size", 12)
 	v.set_anchors_and_offsets_preset(Control.PRESET_BOTTOM_RIGHT)