feat: Add agent workspace system and runtime management

- Add agent core modules (agent_core, factory, registry, skill_loader)
- Add runtime system for agent execution management
- Add REST API for agents, workspaces, and runtime control
- Add process supervisor for agent lifecycle management
- Add workspace template system with agent profiles
- Add frontend RuntimeView and runtime API integration
- Add per-agent skill workspaces for smoke_fullstack run
- Refactor skill system with active/installed separation

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

backend/core/scheduler.py

@@ -38,6 +38,7 @@ class Scheduler:
 
         self.running = False
         self._task: Optional[asyncio.Task] = None
+        self._callback: Optional[Callable] = None
 
     def _now_nyse(self) -> datetime:
         """Get current time in NYSE timezone"""
@@ -68,18 +69,69 @@ class Scheduler:
             return
 
         self.running = True
-
-        if self.mode == "daily":
-            self._task = asyncio.create_task(self._run_daily(callback))
-        elif self.mode == "intraday":
-            self._task = asyncio.create_task(self._run_intraday(callback))
-        else:
-            raise ValueError(f"Unknown scheduler mode: {self.mode}")
+        self._callback = callback
+        self._schedule_task()
 
         logger.info(
             f"Scheduler started: mode={self.mode}, timezone=America/New_York",
         )
 
+    def _schedule_task(self):
+        """Create the active scheduler task for the current mode."""
+        if not self._callback:
+            raise ValueError("Scheduler callback is not set")
+
+        if self._task:
+            self._task.cancel()
+            self._task = None
+
+        if self.mode == "daily":
+            self._task = asyncio.create_task(self._run_daily(self._callback))
+        elif self.mode == "intraday":
+            self._task = asyncio.create_task(
+                self._run_intraday(self._callback),
+            )
+        else:
+            raise ValueError(f"Unknown scheduler mode: {self.mode}")
+
+    def reconfigure(
+        self,
+        *,
+        mode: Optional[str] = None,
+        trigger_time: Optional[str] = None,
+        interval_minutes: Optional[int] = None,
+    ) -> bool:
+        """Update scheduler parameters in-place and restart its timing loop."""
+        changed = False
+
+        if mode and mode != self.mode:
+            self.mode = mode
+            changed = True
+
+        if trigger_time and trigger_time != self.trigger_time:
+            self.trigger_time = trigger_time
+            self.trigger_now = self.trigger_time == "now"
+            changed = True
+
+        if (
+            interval_minutes is not None
+            and interval_minutes > 0
+            and interval_minutes != self.interval_minutes
+        ):
+            self.interval_minutes = interval_minutes
+            changed = True
+
+        if changed and self.running and self._callback:
+            self._schedule_task()
+            logger.info(
+                "Scheduler reconfigured: mode=%s, trigger_time=%s, interval_minutes=%s",
+                self.mode,
+                self.trigger_time,
+                self.interval_minutes,
+            )
+
+        return changed
+
     async def _run_daily(self, callback: Callable):
         """Run once per trading day at specified time (NYSE timezone)"""
         first_run = True