feat(docker): add watch mode for automatic frontend rebuilds in Docker

Makefile

@@ -142,6 +142,22 @@ frontend-build: frontend-tooling ## Build frontend (next build)
 api-gen: frontend-tooling ## Regenerate TS API client (requires backend running at 127.0.0.1:8000)
 	$(NODE_WRAP) --cwd $(FRONTEND_DIR) npm run api:gen
 
+.PHONY: docker-up
+docker-up: ## Start full Docker stack with image rebuild
+	docker compose -f compose.yml --env-file .env up -d --build
+
+.PHONY: docker-watch
+docker-watch: ## Start stack in watch mode (auto rebuild frontend on UI changes)
+	docker compose -f compose.yml --env-file .env up --build --watch
+
+.PHONY: docker-watch-only
+docker-watch-only: ## Attach file watch to an already-running stack
+	docker compose -f compose.yml --env-file .env watch
+
+.PHONY: docker-down
+docker-down: ## Stop full Docker stack
+	docker compose -f compose.yml --env-file .env down
+
 .PHONY: rq-worker
 rq-worker: ## Run background queue worker loop
 	cd $(BACKEND_DIR) && uv run python ../scripts/rq worker

README.md

@@ -100,6 +100,36 @@ Before startup:
 docker compose -f compose.yml --env-file .env up -d --build
 ```
 
+If you are iterating on the UI in Docker and want automatic frontend rebuilds on
+source changes, run:
+
+```bash
+docker compose -f compose.yml --env-file .env up --build --watch
+```
+
+Notes:
+
+- Compose Watch requires Docker Compose **2.22.0+**.
+- You can also run watch separately after startup:
+
+```bash
+docker compose -f compose.yml --env-file .env up -d --build
+docker compose -f compose.yml --env-file .env watch
+```
+
+After pulling new changes, rebuild and recreate all services:
+
+```bash
+docker compose -f compose.yml --env-file .env up -d --build --force-recreate
+```
+
+For a fully clean rebuild (no cached build layers):
+
+```bash
+docker compose -f compose.yml --env-file .env build --no-cache --pull
+docker compose -f compose.yml --env-file .env up -d --force-recreate
+```
+
 ### 3. Open the application
 
 - Mission Control UI: http://localhost:3000

compose.yml

@@ -70,6 +70,23 @@ services:
       - backend
     ports:
       - "${FRONTEND_PORT:-3000}:3000"
+    develop:
+      watch:
+        # Rebuild frontend image when UI source or build config changes.
+        - action: rebuild
+          path: ./frontend/src
+        - action: rebuild
+          path: ./frontend/package.json
+        - action: rebuild
+          path: ./frontend/package-lock.json
+        - action: rebuild
+          path: ./frontend/next.config.ts
+        - action: rebuild
+          path: ./frontend/postcss.config.js
+        - action: rebuild
+          path: ./frontend/tailwind.config.cjs
+        - action: rebuild
+          path: ./frontend/tsconfig.json
 
   webhook-worker:
     build: