feat: add headless browser toggle to settings UI

Replace the PLAYWRIGHT_HEADLESS environment variable with a global
setting toggle in the Settings modal. The setting is persisted in the
registry DB and injected as an env var into agent subprocesses, so
client.py reads it unchanged.

Backend:
- Add playwright_headless field to SettingsResponse/SettingsUpdate schemas
- Read/write the setting in settings router via existing _parse_bool helper
- Pass playwright_headless from agent router through to process manager
- Inject PLAYWRIGHT_HEADLESS env var into subprocess environment

Frontend:
- Add playwright_headless to Settings/SettingsUpdate TypeScript types
- Add "Headless Browser" Switch toggle below YOLO mode in SettingsModal
- Add default value to DEFAULT_SETTINGS in useProjects

Also fix CSS build warning: change @import url("tw-animate-css") to bare
@import "tw-animate-css" so Tailwind v4 inlines it during compilation
instead of leaving it for Vite/Lightning CSS post-processing.

Remove stale summary.md from previous refactoring session.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

server/routers/agent.py

@@ -17,11 +17,11 @@ from ..utils.project_helpers import get_project_path as _get_project_path
 from ..utils.validation import validate_project_name
 
 
-def _get_settings_defaults() -> tuple[bool, str, int]:
+def _get_settings_defaults() -> tuple[bool, str, int, bool]:
     """Get defaults from global settings.
 
     Returns:
-        Tuple of (yolo_mode, model, testing_agent_ratio)
+        Tuple of (yolo_mode, model, testing_agent_ratio, playwright_headless)
     """
     import sys
     root = Path(__file__).parent.parent.parent
@@ -40,7 +40,9 @@ def _get_settings_defaults() -> tuple[bool, str, int]:
     except (ValueError, TypeError):
         testing_agent_ratio = 1
 
-    return yolo_mode, model, testing_agent_ratio
+    playwright_headless = (settings.get("playwright_headless") or "true").lower() == "true"
+
+    return yolo_mode, model, testing_agent_ratio, playwright_headless
 
 
 router = APIRouter(prefix="/api/projects/{project_name}/agent", tags=["agent"])
@@ -89,7 +91,7 @@ async def start_agent(
     manager = get_project_manager(project_name)
 
     # Get defaults from global settings if not provided in request
-    default_yolo, default_model, default_testing_ratio = _get_settings_defaults()
+    default_yolo, default_model, default_testing_ratio, playwright_headless = _get_settings_defaults()
 
     yolo_mode = request.yolo_mode if request.yolo_mode is not None else default_yolo
     model = request.model if request.model else default_model
@@ -101,6 +103,7 @@ async def start_agent(
         model=model,
         max_concurrency=max_concurrency,
         testing_agent_ratio=testing_agent_ratio,
+        playwright_headless=playwright_headless,
     )
 
     # Notify scheduler of manual start (to prevent auto-stop during scheduled window)

server/routers/settings.py

@@ -91,6 +91,7 @@ async def get_settings():
         glm_mode=_is_glm_mode(),
         ollama_mode=_is_ollama_mode(),
         testing_agent_ratio=_parse_int(all_settings.get("testing_agent_ratio"), 1),
+        playwright_headless=_parse_bool(all_settings.get("playwright_headless"), default=True),
     )
 
 
@@ -106,6 +107,9 @@ async def update_settings(update: SettingsUpdate):
     if update.testing_agent_ratio is not None:
         set_setting("testing_agent_ratio", str(update.testing_agent_ratio))
 
+    if update.playwright_headless is not None:
+        set_setting("playwright_headless", "true" if update.playwright_headless else "false")
+
     # Return updated settings
     all_settings = get_all_settings()
     return SettingsResponse(
@@ -114,4 +118,5 @@ async def update_settings(update: SettingsUpdate):
         glm_mode=_is_glm_mode(),
         ollama_mode=_is_ollama_mode(),
         testing_agent_ratio=_parse_int(all_settings.get("testing_agent_ratio"), 1),
+        playwright_headless=_parse_bool(all_settings.get("playwright_headless"), default=True),
     )

server/schemas.py

@@ -398,6 +398,7 @@ class SettingsResponse(BaseModel):
     glm_mode: bool = False  # True if GLM API is configured via .env
     ollama_mode: bool = False  # True if Ollama API is configured via .env
     testing_agent_ratio: int = 1  # Regression testing agents (0-3)
+    playwright_headless: bool = True
 
 
 class ModelsResponse(BaseModel):
@@ -411,6 +412,7 @@ class SettingsUpdate(BaseModel):
     yolo_mode: bool | None = None
     model: str | None = None
     testing_agent_ratio: int | None = None  # 0-3
+    playwright_headless: bool | None = None
 
     @field_validator('model')
     @classmethod

server/services/process_manager.py

@@ -297,6 +297,7 @@ class AgentProcessManager:
         parallel_mode: bool = False,
         max_concurrency: int | None = None,
         testing_agent_ratio: int = 1,
+        playwright_headless: bool = True,
     ) -> tuple[bool, str]:
         """
         Start the agent as a subprocess.
@@ -307,6 +308,7 @@ class AgentProcessManager:
             parallel_mode: DEPRECATED - ignored, always uses unified orchestrator
             max_concurrency: Max concurrent coding agents (1-5, default 1)
             testing_agent_ratio: Number of regression testing agents (0-3, default 1)
+            playwright_headless: If True, run browser in headless mode
 
         Returns:
             Tuple of (success, message)
@@ -358,7 +360,7 @@ class AgentProcessManager:
                 "stdout": subprocess.PIPE,
                 "stderr": subprocess.STDOUT,
                 "cwd": str(self.project_dir),
-                "env": {**os.environ, "PYTHONUNBUFFERED": "1"},
+                "env": {**os.environ, "PYTHONUNBUFFERED": "1", "PLAYWRIGHT_HEADLESS": "true" if playwright_headless else "false"},
             }
             if sys.platform == "win32":
                 popen_kwargs["creationflags"] = subprocess.CREATE_NO_WINDOW