## Why
`multi_agents_v2` is meant to be independently gated from the older
`collab` feature. The tool registry still treated the
collaboration-style agent tools as `collab`-only, so enabling
`multi_agents_v2` without `collab` omitted the v2 agent tools. Review
and guardian sub-sessions also need to keep agent spawning disabled even
when the outer session has `multi_agents_v2` enabled.
## What changed
- Include the collab-backed agent tools when either `multi_agents_v2` or
`collab` is enabled.
- Explicitly disable `multi_agents_v2` for review and guardian review
sub-sessions, matching the existing `spawn_csv` and `collab`
restrictions.
- Add a registry test that enables `multi_agents_v2`, disables `collab`,
and verifies the v2 agent tools are present while legacy `send_input`
and `resume_agent` remain hidden.
## Testing
- Added
`test_build_specs_multi_agent_v2_does_not_require_collab_feature`.
## Why
Fixes#20145.
`config/value/write` treats a JSON `null` value as a request to clear
the config key. Clearing a key that is already absent should be
idempotent, but clearing a nested key such as `features.personality`
from an empty `config.toml` returned `configPathNotFound` because
`clear_path` treated the missing `features` parent table as an error.
That makes app-server reset flows brittle because clients have to read
first and avoid sending a clear request unless the parent path already
exists.
## What Changed
- Updated app-server config clearing so missing intermediate tables, or
non-table parents, are treated as an unchanged no-op.
- Removed the now-unreachable `MergeError::PathNotFound` path from
config write merging.
- Added a regression test covering `features.personality = null` against
an empty user config.
## Verification
- `cargo test -p codex-app-server clear_missing_nested_config_is_noop`
- `cargo test -p codex-app-server` was run; the config manager unit
suite passed, but one unrelated integration test failed because
`turn_start_emits_thread_scoped_warning_notification_for_trimmed_skills`
expected `7` trimmed skills and observed `8`.
- `just fix -p codex-app-server`
1. Adds v2 plugin/share/save, plugin/share/list, and plugin/share/delete
RPCs.
2. Implements save by archiving a local plugin root, enforcing a size
limit, uploading through the workspace upload flow, and supporting
updates via remotePluginId.
3. Lists created workspace plugins
4. Deletes a previously uploaded/shared plugin.
