feat: harden remote serve and reuse connections

- Gate TCP serve commands with safe-by-default policies, per-key allow tokens, per-key rate limiting, and audit labels.
- Reuse authenticated encrypted remote sessions and parallelize/caches multi-browser fanout to reduce repeated handshake roundtrips.
- Increase paged native-host batch size with extension-side byte budgeting to speed large tab listings safely.
- Point install output at public Chrome Web Store / Firefox AMO listings by default, with --dev preserving unpacked workflows.
- Share search-engine metadata between CLI and SDK and bump the package/extension version to 0.16.0.
- Cover the new security, pooling, paging, install, and fanout behavior with expanded Python and extension tests.

browser_cli/commands/doctor.py

@@ -1,35 +1,18 @@
 from __future__ import annotations
 
-import re
 import shutil
-from importlib.metadata import PackageNotFoundError, version as package_version
-from pathlib import Path
-
 import click
 from rich.console import Console
 from rich.table import Table
 
 from browser_cli.commands import handle_errors, client_from_ctx
 from browser_cli.client import active_browser_targets
-from browser_cli.constants import NATIVE_HOST_DIRS, NATIVE_HOST_NAME, PYPI_PACKAGE_NAME
+from browser_cli.constants import NATIVE_HOST_DIRS, NATIVE_HOST_NAME
 from browser_cli.platform import is_windows
+from browser_cli.version_manager import project_version
 
 console = Console()
 
-def _project_version() -> str:
-    pyproject_path = Path(__file__).resolve().parents[2] / "pyproject.toml"
-    try:
-        content = pyproject_path.read_text(encoding="utf-8")
-        match = re.search(r'^version\s*=\s*"([^"]+)"', content, re.MULTILINE)
-        if match:
-            return match.group(1)
-    except OSError:
-        pass
-    try:
-        return package_version(PYPI_PACKAGE_NAME)
-    except PackageNotFoundError:
-        return "unknown"
-
 def _status(ok: bool) -> str:
     return "[green]OK[/green]" if ok else "[red]FAIL[/red]"
 
@@ -39,7 +22,7 @@ def _status(ok: bool) -> str:
 def cmd_doctor(check_remote):
     """Diagnose browser-cli installation, extension, and connection health."""
     rows: list[tuple[str, bool, str]] = []
-    version = _project_version()
+    version = project_version()
     rows.append(("Python package", version != "unknown", version))
     rows.append(("browser-cli executable", shutil.which("browser-cli") is not None, shutil.which("browser-cli") or "not on PATH"))