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/version_manager.py

@@ -1,17 +1,33 @@
-from importlib.metadata import version as _pkg_version
+from importlib.metadata import PackageNotFoundError, version as _pkg_version
+from pathlib import Path
 
 from browser_cli.constants import MAX_MSG_BYTES, PROTOCOL_MIN_CLIENT, PYPI_PACKAGE_NAME
 
 def parse_version(v: str) -> tuple[int, ...]:
-    try:
-        return tuple(int(x) for x in v.lstrip("v").split("."))
-    except ValueError:
-        return (0,)
+  try:
+    return tuple(int(x) for x in v.lstrip("v").split("."))
+  except ValueError:
+    return (0,)
 
 def get_installed_version() -> str:
-    try:
-        return _pkg_version(PYPI_PACKAGE_NAME)
-    except Exception:
-        return "0.0.0"
+  try:
+    return _pkg_version(PYPI_PACKAGE_NAME)
+  except Exception:
+    return "0.0.0"
+
+def project_version() -> str:
+  pyproject_path = Path(__file__).resolve().parent.parent / "pyproject.toml"
+  try:
+    content = pyproject_path.read_text(encoding="utf-8")
+    for line in content.splitlines():
+      if line.startswith("version = "):
+        return line.split('"')[1]
+  except OSError:
+    pass
+
+  try:
+    return _pkg_version(PYPI_PACKAGE_NAME)
+  except PackageNotFoundError:
+    return "unknown"
 
 USER_AGENT = f"browser-cli/{get_installed_version()}"