fix(update): drop the --reinstall plumbing; a plain editable install already rewrites the finder

Review fix for #119525. The stale-map detection stays; the forced
`--reinstall` goes, for three reasons verified live:

- uv (0.12.13, the version the updater ships) reinstalls an editable
  source tree on every `uv pip install -e .` (`~ hermes-agent==0.21.4`
  even with no change). Adding a root module and running the plain
  install rewrote the finder MAPPING without touching packaging files,
  so once the skip is refused the existing install already refreshes it.
- `--reinstall` reinstalls EVERY package in the venv, not just
  hermes-agent; the narrow spelling would be `--reinstall-package
  hermes-agent`, and neither is needed.
- `--reinstall` is not a pip option. On the pip fallback path (no uv:
  Termux without uv, some site-packages installs) a stale map turned the
  update into a hard `no such option` failure, worse than the skip.

Also removes the second `_editable_finder_mapping_current` call in
`_sync_python_dependencies_after_pull` (the predicate already ran it)
and the flag's test.

hermes_cli/main_install_repair.py

@@ -951,8 +951,7 @@ def _interpreter_scripts_dir() -> Path | None:
 
 
 def _install_python_dependencies_with_optional_fallback(
-    install_cmd_prefix: list[str], *, env: dict[str, str] | None = None, group: str = "all",
-    reinstall: bool = False,
+    install_cmd_prefix: list[str], *, env: dict[str, str] | None = None, group: str = "all"
 ) -> None:
     """Install base deps plus as many optional extras as the environment supports.
 
@@ -981,8 +980,6 @@ def _install_python_dependencies_with_optional_fallback(
             scripts_dir = _interpreter_scripts_dir()
 
     def _install(args: list[str]) -> None:
-        if reinstall:
-            args = [args[0], "--reinstall", *args[1:]]
         if pin_python:
             args = _insert_python_pin(args)
         # strict_quarantine: this is the UPDATE dependency sync; ShimQuarantineError propagates

hermes_cli/update_cmd_deps.py

@@ -1199,7 +1199,6 @@ def _sync_python_dependencies_after_pull(
     # by the next launch (``_recover_from_interrupted_install``). Lazy refresh uses its own marker.
     _write_update_incomplete_marker()
     deps_current = _editable_install_is_current(git_cmd, _m().PROJECT_ROOT, pre_pull_sha)
-    mapping_current = _editable_finder_mapping_current(_m().PROJECT_ROOT)
     print(
         "→ Python dependencies unchanged — skipping reinstall" if deps_current
         else "→ Updating Python dependencies...")
@@ -1232,8 +1231,7 @@ def _sync_python_dependencies_after_pull(
             print("  → Termux/Android detected: prebuilding psutil with Linux source path compatibility...")
             _install_psutil_android_compat(install_prefix, env=lazy_env)
         _m()._install_python_dependencies_with_optional_fallback(
-            install_prefix, env=lazy_env, group=install_group,
-            reinstall=mapping_current is False)
+            install_prefix, env=lazy_env, group=install_group)
 
     # Clear the core breadcrumb before lazy refresh, which uses its own marker so a lazy
     # failure can't be "healed" by a narrow core import probe.

tests/hermes_cli/test_update_skip_unchanged_editable_install.py

@@ -116,30 +116,6 @@ def test_unreadable_finder_fails_closed(repo, monkeypatch):
     assert _editable_install_is_current(GIT, repo, before) is False
 
 
-def test_mapping_drift_requests_reinstall_flag():
-    from hermes_cli.main_install_repair import _install_python_dependencies_with_optional_fallback
-
-    recorded = []
-    monkeypatch = pytest.MonkeyPatch()
-    monkeypatch.setattr(
-        "hermes_cli.main_install_repair._run_quarantined_install",
-        lambda cmd, **kwargs: recorded.append(cmd),
-    )
-    monkeypatch.setattr(
-        "hermes_cli.main_install_repair._verify_console_scripts_installed",
-        lambda *args, **kwargs: None,
-    )
-    monkeypatch.setattr("hermes_cli.main_install_repair._is_windows", lambda: False)
-    try:
-        _install_python_dependencies_with_optional_fallback(["uv", "pip"], reinstall=True)
-        assert recorded and "--reinstall" in recorded[0]
-        recorded.clear()
-        _install_python_dependencies_with_optional_fallback(["uv", "pip"], reinstall=False)
-        assert recorded and "--reinstall" not in recorded[0]
-    finally:
-        monkeypatch.undo()
-
-
 def test_source_only_pull_skips_the_reinstall(repo):
     """The common update: .py churn inside already-mapped packages."""
     before = _head(repo)