fix(dockerfile): pre-create .langgraph_api to prevent tsx watch restart loop

langgraph/Dockerfile

@@ -12,9 +12,11 @@ RUN pnpm install --frozen-lockfile
 # Copy source code
 COPY . .
 
-# langgraphjs dev requires a .env file to exist (even if empty)
-# Real env vars are injected by Azure Container App at runtime
-RUN touch .env
+# langgraphjs dev requires .env to exist, and writes .langgraph_api + .gitignore on startup
+# Pre-create these to prevent tsx file watcher from triggering a restart loop
+RUN touch .env && \
+    mkdir -p .langgraph_api && \
+    echo ".langgraph_api" >> .gitignore
 
 # Expose LangGraph server port
 EXPOSE 2024