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/commands/session.py

@@ -4,12 +4,10 @@ from rich.console import Console
 
 console = Console()
 
-
 @click.group("session")
 def session_group():
     """Save and restore browser sessions."""
 
-
 @session_group.command("save")
 @click.argument("name")
 def session_save(name):
@@ -18,16 +16,29 @@ def session_save(name):
     count = result.get("tabs", 0) if isinstance(result, dict) else 0
     console.print(f"[green]Session '{name}' saved[/green] ({count} tabs)")
 
-
 @session_group.command("load")
 @click.argument("name")
-def session_load(name):
+@click.option("--gentle-mode", type=click.Choice(["auto", "normal", "gentle", "ultra"]), default="auto", show_default=True, help="Throttle mode for large restores.")
+@click.option("--discard-background-tabs", is_flag=True, help="Discard restored background tabs after opening to reduce load.")
+@click.option("--lazy", is_flag=True, help="Create lightweight placeholder tabs after --eager-tabs; placeholders load when selected.")
+@click.option("--eager-tabs", type=int, default=10, show_default=True, help="Number of real tabs to open before lazy placeholders.")
+@click.option("--background", "background_job", is_flag=True, help="Start restore as a background job and return immediately.")
+def session_load(name, gentle_mode, discard_background_tabs, lazy, eager_tabs, background_job):
     """Restore session NAME (opens all saved tabs)."""
-    result = _handle("session.load", {"name": name})
+    result = _handle("session.load", {
+        "name": name,
+        "gentleMode": gentle_mode,
+        "discardBackgroundTabs": discard_background_tabs,
+        "lazy": lazy,
+        "eagerTabs": eager_tabs,
+        "__background": background_job,
+    })
+    if background_job and isinstance(result, dict) and result.get("jobId"):
+        console.print(f"[green]Session restore started[/green] job={result['jobId']}")
+        return
     count = result.get("tabs", 0) if isinstance(result, dict) else 0
     console.print(f"[green]Session '{name}' loaded[/green] ({count} tabs opened)")
 
-
 @session_group.command("diff")
 @click.argument("name_a")
 @click.argument("name_b")
@@ -54,7 +65,6 @@ def session_diff(name_a, name_b):
     if not added and not removed:
         console.print("[green]Sessions are identical[/green]")
 
-
 @session_group.command("list")
 def session_list():
     """List all saved sessions."""
@@ -90,7 +100,6 @@ def session_list():
         table.add_row(*row)
     console.print(table)
 
-
 @session_group.command("remove")
 @click.argument("name")
 def session_remove(name):
@@ -98,6 +107,24 @@ def session_remove(name):
     _handle("session.remove", {"name": name})
     console.print(f"[green]Session '{name}' removed[/green]")
 
+@session_group.command("job-status")
+@click.argument("job_id")
+def session_job_status(job_id):
+    """Show status for a background session job."""
+    result = _handle("jobs.status", {"jobId": job_id}) or {}
+    status = result.get("status", "unknown")
+    console.print(f"[bold]{job_id}[/bold]: {status}")
+    if result.get("error"):
+        console.print(f"[red]{result['error']}[/red]")
+    elif result.get("result"):
+        console.print(result["result"])
+
+@session_group.command("job-cancel")
+@click.argument("job_id")
+def session_job_cancel(job_id):
+    """Cancel a running background job."""
+    _handle("jobs.cancel", {"jobId": job_id})
+    console.print(f"[green]Cancel requested for {job_id}[/green]")
 
 @session_group.command("auto-save")
 @click.argument("state", type=click.Choice(["on", "off"]))