feat(daemon): add core asyncio daemon, supervisor, and registry factories

- core.py: asyncio event loop entry point, PluginSupervisor with per-task
  restart (up to 10 times, 5s back-off), IPC dispatch, signal handling
  (SIGTERM/SIGHUP on POSIX), RotatingFileHandler, start_background() helper
- daemon/__init__.py: export public API
- plugins/registry.py: add get_daemon_task_factories() so supervisor can
  restart crashed tasks by re-calling plugin.daemon_tasks()[i]
- config/schema.py: add DaemonConfig.ipc_port for Windows TCP loopback

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

src/pyra/plugins/registry.py

@@ -75,6 +75,29 @@ class PluginRegistry:
                 pass
         return tasks
 
+    def get_daemon_task_factories(
+        self,
+    ) -> list[tuple[str, Callable[[], Coroutine]]]:  # type: ignore[type-arg]
+        """Return (name, factory) pairs for all plugin daemon tasks.
+
+        Each factory re-calls plugin.daemon_tasks() to produce a fresh coroutine,
+        enabling the supervisor to restart crashed tasks without changing the plugin
+        protocol.
+        """
+        factories: list[tuple[str, Callable[[], Coroutine]]] = []  # type: ignore[type-arg]
+        for plugin in self._plugins.values():
+            try:
+                n_tasks = len(plugin.daemon_tasks())
+            except Exception:
+                continue
+            for i in range(n_tasks):
+                name = f"{plugin.name}.task_{i}"
+                # Capture plugin and index by value so each closure is independent.
+                def _factory(p=plugin, idx=i) -> Coroutine:  # type: ignore[type-arg]
+                    return p.daemon_tasks()[idx]
+                factories.append((name, _factory))
+        return factories
+
     def find_tool(self, name: str) -> Tool | None:
         return self._tools.get(name)