Review findings on d8c467f223, each reproduced through its production path.
Stale launch key. `strip_launch_profile_env` built its residue set from a
re-parse of the launch `.env`. A key removed or renamed in that file after
boot is still in `os.environ` with the old value (dotenv never unsets), and
the current file no longer names it, so it survived into the routed child.
`_load_dotenv_with_fallback` — the one chokepoint every dotenv load goes
through — now records the KEY names it put into the process env, additive for
the process lifetime (`launch_dotenv_keys()`), and the strip unions that record
with the current file.
Source name that lost to the process env. `_apply_external_secret_sources`
snapshots every name a source SUPPLIED (`provenance` + `skipped_existing`),
but `secret_source_names()` only exposed `_SECRET_SOURCES`, which is
provenance metadata and names applied values alone. A launch-profile source
that supplied `CUSTOM_VAULT_SECRET` while the process already had it was
therefore invisible to the scrub, and a routed child with an empty scope got
the launch value. Supplied names are tracked separately
(`_SOURCE_SUPPLIED_NAMES`) so the provenance labels stay honest, and
`secret_source_names()` returns the union.
Last plugin source removed. `_refresh_secret_sources_after_discovery`
returned before the cache reset and the installed-scope refresh whenever no
plugin source was enabled — and `discover_and_load(force=True)` unloads the
old registration first, so removing the final plugin source hit exactly that
return with the removed plugin's names still in the per-home snapshot and the
current scope. The manager now remembers that a discovery re-applied plugin
sources and, on the next discovery that finds none, reconciles once. A home
that never had a plugin source is still a no-op (pinned by the existing tests).
Regressions: the stale-key lifecycle and the skipped-existing case through
`_run_job_script` against a real routed child, and the removal case through
the manager. Each checked by reverting its fix and confirming the test fails.
(cherry picked from commit d464f5f6126a394cfb47937f683d3a5e2f141840)
9d7de6c140