fix: restore Python 3.10/3.11 support and report MCP version

- Drop backslash from f-string expression in markdown/html.py
- That syntax needs 3.12+ (PEP 701) and broke import on 3.10/3.11
- Add Python matrix 3.10/3.12/3.14/3.15 to the Gitea testing workflow
- Pass project_version() to MCPServer; serverInfo.version was empty
- Cover the reported version with an in-memory MCP client test
- Swap deprecated click.get_text_stream for sys.stdin.isatty()
- Add explicit encoding to native host shim and manifest writes
- Add explicit encoding to the registry lock file open
- Add explicit encoding to every read_text/write_text call in tests
- Bump version to 0.16.10 in pyproject.toml and extension/manifest.json
- Move .python-version to 3.15 and refresh uv.lock

Extension code is unchanged; only the manifest version string moved.

Verified with 778 tests on 3.10 through 3.15, plus a strict run using -X warn_default_encoding with EncodingWarning and DeprecationWarning as errors.

tests/test_client.py

@@ -41,7 +41,7 @@ def test_resolve_socket_uses_only_active_registry_entry(monkeypatch, tmp_path):
   socket_path = tmp_path / "browser.sock"
   listener = _listening_unix_socket(socket_path)
   registry_path = tmp_path / "registry.json"
-  registry_path.write_text(json.dumps({"abc-uuid": str(socket_path)}))
+  registry_path.write_text(json.dumps({"abc-uuid": str(socket_path)}), encoding="utf-8")
 
   monkeypatch.setattr("browser_cli.client.targets.REGISTRY_PATH", registry_path)
 
@@ -58,7 +58,7 @@ def test_resolve_socket_raises_when_multiple_active_entries(monkeypatch, tmp_pat
   first_listener = _listening_unix_socket(first_socket)
   second_listener = _listening_unix_socket(second_socket)
   registry_path = tmp_path / "registry.json"
-  registry_path.write_text(json.dumps({"uuid-1": str(first_socket), "uuid-2": str(second_socket)}))
+  registry_path.write_text(json.dumps({"uuid-1": str(first_socket), "uuid-2": str(second_socket)}), encoding="utf-8")
 
   monkeypatch.setattr("browser_cli.client.targets.REGISTRY_PATH", registry_path)
 
@@ -87,7 +87,7 @@ def test_active_browser_targets_filters_stale_entries(monkeypatch, tmp_path):
   stale_listener = _listening_unix_socket(stale_socket)
   stale_listener.close()
   registry_path = tmp_path / "registry.json"
-  registry_path.write_text(json.dumps({"work": str(active_socket), "default": str(stale_socket)}))
+  registry_path.write_text(json.dumps({"work": str(active_socket), "default": str(stale_socket)}), encoding="utf-8")
 
   monkeypatch.setattr("browser_cli.client.targets.REGISTRY_PATH", registry_path)
 
@@ -102,7 +102,7 @@ def test_active_browser_targets_filters_stale_entries(monkeypatch, tmp_path):
 
 def test_active_browser_targets_keeps_windows_registry_entries(monkeypatch, tmp_path):
   registry_path = tmp_path / "registry.json"
-  registry_path.write_text(json.dumps({"work": r"\\.\pipe\browser-cli-work"}))
+  registry_path.write_text(json.dumps({"work": r"\\.\pipe\browser-cli-work"}), encoding="utf-8")
 
   monkeypatch.setattr("browser_cli.client.targets.REGISTRY_PATH", registry_path)
   monkeypatch.setattr("browser_cli.client.targets.is_windows", lambda: True)
@@ -174,7 +174,7 @@ def test_send_command_prefers_active_local_profile_over_saved_remote_alias(monke
   monkeypatch.delenv("BROWSER_CLI_REMOTE", raising=False)
   monkeypatch.delenv("BROWSER_CLI_PROFILE", raising=False)
   socket_path = tmp_path / "work.sock"
-  socket_path.write_text("")
+  socket_path.write_text("", encoding="utf-8")
   registry_path = tmp_path / "registry.json"
   registry_path.write_text(json.dumps({"work": str(socket_path)}), encoding="utf-8")
   monkeypatch.setattr("browser_cli.client.targets.REGISTRY_PATH", registry_path)