feat(client): permanent dialogue panel + protocol v13 + build check

- dialogue_box.gd: panel is always visible as permanent insert UI
  element per D-061 — content fades but frame stays on screen
- protocol.gd: bump PROTOCOL_VERSION to 13
- Makefile: add check-protocol target that verifies server/client
  protocol versions match, runs automatically before build

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

Makefile

@@ -1,6 +1,6 @@
 GODOT := $(shell command -v godot4 2>/dev/null || command -v godot 2>/dev/null)
 
-.PHONY: help setup build client server game stop test lint ci ci-client ci-server clean \
+.PHONY: help setup build check-protocol client server game stop test lint ci ci-client ci-server clean \
        decisions-sync decisions-coverage decisions-active decisions-orphan \
        db-backup db-install validate-content content-ron check-fact-ids setup-hooks \
        pre-pr pre-pr-lint pre-pr-build pre-pr-test pre-pr-validate pre-pr-fixtures \
@@ -28,6 +28,7 @@ help:
 	@echo "  make ci             Run full CI pipeline locally"
 	@echo "  make ci-client      Run client CI checks"
 	@echo "  make ci-server      Run server CI checks"
+	@echo "  make check-protocol Verify server/client protocol versions match"
 	@echo "  make clean          Remove build artifacts and caches"
 	@echo ""
 	@echo "  make db-backup          Backup shared database to git (main only)"
@@ -82,7 +83,16 @@ setup-hooks:
 
 # --- Build ---
 
-build: build-server build-client
+check-protocol:
+	@SERVER_V=$$(grep 'pub const PROTOCOL_VERSION' server/src/bridge/types.rs | sed 's/.*= *//;s/[^0-9]//g'); \
+	CLIENT_V=$$(grep 'const PROTOCOL_VERSION' client/scripts/protocol/protocol.gd | sed 's/.*= *//;s/[^0-9]//g'); \
+	if [ "$$SERVER_V" != "$$CLIENT_V" ]; then \
+		echo "ERROR: Protocol version mismatch — server=$$SERVER_V, client=$$CLIENT_V"; \
+		echo "  Fix: update client/scripts/protocol/protocol.gd to match server/src/bridge/types.rs"; \
+		exit 1; \
+	fi
+
+build: check-protocol build-server build-client
 
 build-server:
 	cd server && cargo build

client/scripts/protocol/protocol.gd

@@ -11,7 +11,7 @@ class_name Protocol
 
 ## Protocol version — must match server PROTOCOL_VERSION in bridge/types.rs.
 ## Reject snapshots where version != this value.
-const PROTOCOL_VERSION: int = 12
+const PROTOCOL_VERSION: int = 13
 
 
 # -- Decode: bytes from server → GDScript types --------------------------------

client/ui/dialogue_box.gd

@@ -41,7 +41,6 @@ var _option_is_confrontation: Array[bool] = []
 var _npc_name: String = ""
 
 # -- UI state --
-var _is_showing: bool = false
 var _active_tween: Tween = null
 var _beat_tween: Tween = null  # D-063: confrontation beat delay
 
@@ -77,9 +76,10 @@ const _WALK_AWAY_ACTIONS: Array[StringName] = [
 
 
 func _ready() -> void:
-	panel.modulate.a = 0.0
-	visible = false
-	_is_showing = false
+	# Panel is always visible as a permanent insert UI element (D-061).
+	# Content fades in/out but the panel frame stays on screen.
+	visible = true
+	panel.modulate.a = 1.0
 	mouse_filter = Control.MOUSE_FILTER_IGNORE
 	_load_theme()
 	_update_layout()
@@ -94,8 +94,6 @@ func _process(_delta: float) -> void:
 
 
 func _unhandled_input(event: InputEvent) -> void:
-	if not _is_showing:
-		return
 	if not _in_player_conversation:
 		return
 
@@ -327,25 +325,13 @@ func _end_player_conversation() -> void:
 		hide_dialogue()
 
 
-## Hide the entire panel with fade.
+## End active dialogue state. Panel stays visible (permanent insert UI element).
 func hide_dialogue() -> void:
-	if not _is_showing:
-		return
-
 	if _in_player_conversation:
 		_end_player_conversation()
 		return  # _end_player_conversation may call hide_dialogue if log is empty
 
-	_is_showing = false
-
-	if _active_tween and _active_tween.is_valid():
-		_active_tween.kill()
-	_active_tween = create_tween()
-	_active_tween.tween_property(panel, "modulate:a", 0.0, FADE_OUT)
-	_active_tween.tween_callback(func():
-		visible = false
-		GameState.dialogue_active = false  # D-064: unblock movement after fade completes
-	)
+	GameState.dialogue_active = false
 
 
 func is_dialogue_active() -> bool:
@@ -621,16 +607,9 @@ func _expire_entries() -> void:
 
 # -- Visibility --
 
-## Ensure panel is visible (fade in if needed).
+## No-op — panel is always visible as a permanent insert UI element.
 func _ensure_visible() -> void:
-	if _is_showing:
-		return
-	visible = true
-	_is_showing = true
-	if _active_tween and _active_tween.is_valid():
-		_active_tween.kill()
-	_active_tween = create_tween()
-	_active_tween.tween_property(panel, "modulate:a", 1.0, FADE_IN)
+	pass
 
 
 func _clear_options() -> void: