## Why
Unsupported untrusted approval policies must remain startup errors even when
app-server is allowed to fall back from other invalid configuration. Likewise,
compound command summaries must not discard a `sed` stage that can edit files
in place.
## What changed
- Propagate `UnsupportedUntrustedApprovalPolicyError` from both app-server
configuration loads instead of replacing it with default configuration.
- Parse `sed` options through `--`, option arguments, combined short flags, and
backup suffixes so `-i`/`--in-place` commands remain unknown actions.
- Keep non-mutating `sed` operands after `--` from being mistaken for flags.
## Testing
Added parser coverage for in-place `sed` variants in compound commands and for
dash-prefixed operands after `--`.
GitOrigin-RevId: 112ead912e10fcb6c7dd0ede4bf84e390af82da8
jif
f277e313f1