feat: add performance controls for large browser ops

- Add throttled large-operation handling for tab, group, and session commands.
- Introduce performance profiles, audible-tab aware gentle mode, and job progress tracking.
- Support background session restores with status/cancel commands and lazy placeholders.
- Expose new perf and extension CLI groups plus matching Python SDK methods.
- Preserve pinned tabs during session snapshots and debounce auto-save updates.
- Bump browser-cli and extension versions to 0.10.0 and add pytest-cov to dev deps.
- Add coverage for performance controls, background jobs, lazy restores, and tab metadata.

browser_cli/__init__.py

@@ -758,8 +758,61 @@ class BrowserCLI:
     def session_save(self, name: str) -> None:
         self._cmd("session.save", {"name": name})
 
-    def session_load(self, name: str) -> None:
-        self._cmd("session.load", {"name": name})
+    def session_load(
+        self,
+        name: str,
+        *,
+        gentle_mode: str = "auto",
+        discard_background_tabs: bool = False,
+        lazy: bool = False,
+        eager_tabs: int = 10,
+    ) -> None:
+        self._cmd("session.load", {
+            "name": name,
+            "gentleMode": gentle_mode,
+            "discardBackgroundTabs": discard_background_tabs,
+            "lazy": lazy,
+            "eagerTabs": eager_tabs,
+        })
+
+    def session_load_background(
+        self,
+        name: str,
+        *,
+        gentle_mode: str = "auto",
+        discard_background_tabs: bool = False,
+        lazy: bool = False,
+        eager_tabs: int = 10,
+    ) -> dict:
+        return self._cmd("session.load", {
+            "name": name,
+            "gentleMode": gentle_mode,
+            "discardBackgroundTabs": discard_background_tabs,
+            "lazy": lazy,
+            "eagerTabs": eager_tabs,
+            "__background": True,
+        }) or {}
+
+    def job_status(self, job_id: str) -> dict:
+        return self._cmd("jobs.status", {"jobId": job_id}) or {}
+
+    def job_cancel(self, job_id: str) -> dict:
+        return self._cmd("jobs.cancel", {"jobId": job_id}) or {}
+
+    def reload_extension(self) -> None:
+        """Reload the browser-cli extension service worker.
+
+        Schedules a ``chrome.runtime.reload()`` inside the extension and returns
+        immediately.  The extension restarts ~200 ms later and reconnects via the
+        keepalive alarm within ~25 seconds.
+        """
+        self._cmd("extension.reload", {})
+
+    def perf_status(self) -> dict:
+        return self._cmd("perf.status", {}) or {}
+
+    def set_performance_profile(self, profile: str) -> dict:
+        return self._cmd("perf.set_profile", {"profile": profile}) or {}
 
     def session_diff(self, name_a: str, name_b: str) -> dict:
         return self._cmd("session.diff", {"nameA": name_a, "nameB": name_b}) or {}