Fixes the profile-clobber bug cluster at the apply_all() chokepoint so
every secret source — bundled and plugin — gets both behaviors for free:
- secrets.preserve_existing (#58073): env var names whose existing .env /
shell value always wins, even against a source with
override_existing: true. Escape hatch for per-profile platform
secrets while everything else rotates centrally.
- Profile aliasing (#51447): under a named profile, an applied
FOO_<PROFILE> var (credential-shaped suffixes only) also hydrates the
canonical FOO, so adapters/plugins that read fixed env names see the
profile's value. Direct supply beats alias; protected/claimed/
override guards all apply; secrets.profile_alias: false disables.
Reimplements the intent of PR #58085 (tianma-if, preserve_existing on the
legacy Bitwarden apply shim) and PR #51616 (LeonSGP43, profile aliasing
inside the Bitwarden backend) on the SecretSource orchestrator that
superseded those code paths.
Fixes#58073. Fixes#51447.
Co-authored-by: tianma-if <5895871+tianma-if@users.noreply.github.com>
Co-authored-by: LeonSGP43 <154585401+LeonSGP43@users.noreply.github.com>
