## Why
We're moving exec-server to use PathUri for its internal path
representations.
## What
Move `ExecutorFileSystem` APIs to use `PathUri` instead of
`AbsolutePathBuf`. Future changes will convert higher-level parts of
exec-server.
## Why
The skills extension needs to become the path that exposes local host
skills without losing the behavior already owned by core skill loading.
Host skill discovery is not just `$CODEX_HOME/skills`: it also includes
config layers, bundled-skill settings, plugin roots, runtime extra
roots, and the filesystem for the selected primary environment.
Rather than making the extension reload host skills and risk drifting
from that authoritative load, this PR bridges the already-loaded
per-turn skills outcome into the extension. That lets the extension
advertise host skills and inject explicit `$skill` prompts while
preserving the same roots, disabled/hidden state, rendered paths, and
environment-backed file reads that the legacy path uses.
## What Changed
- Adds `HostLoadedSkills` in `core-skills` to wrap the turn's
`SkillLoadOutcome` and read `SKILL.md` through the filesystem that
loaded that skill.
- Stores `HostLoadedSkills` in turn extension data for normal turns and
review turns, so the skills extension can consume the loaded host
catalog without reloading it.
- Adds `HostSkillProvider` under `ext/skills/src/provider/host.rs`,
mapping host-loaded skill metadata into the skills-extension
catalog/read contract.
- Registers the host provider by default from
`codex_skills_extension::install()`.
- Preserves host skill metadata such as dependencies, disabled state,
hidden-from-prompt policy, and slash-normalized display paths.
- Passes host-loaded skills through `SkillListQuery` and
`SkillReadRequest` so explicit skill invocation reads only resources
from the loaded host catalog.
- Adds integration coverage for a real legacy
`$CODEX_HOME/skills/.../SKILL.md` skill being listed and injected
through the installed extension.
## Testing
- Added `installed_extension_loads_host_skills_from_legacy_roots` in
`ext/skills/tests/skills_extension.rs`.
- `just test -p codex-skills-extension`
## Why
Skill metadata accepted a `permissions` block and stored the result on
`SkillMetadata`, but that data was never consumed by runtime behavior.
Leaving the dead parsing path in place makes it look like skills can
widen or otherwise influence execution permissions when, in practice,
declared skill permissions are ignored.
This change removes that misleading surface area so the skill metadata
model matches what the system actually uses.
## What changed
- removed `permission_profile` and `managed_network_override` from
`core-skills::SkillMetadata`
- stopped parsing `permissions` from skill metadata in
`core-skills/src/loader.rs`
- deleted the loader tests that only exercised the removed permissions
parsing path
- cleaned up dependent `SkillMetadata` constructors in tests and TUI
code that were only carrying `None` for those fields
## Testing
- `cargo test -p codex-core-skills`
- `cargo test -p codex-tui
submission_prefers_selected_duplicate_skill_path`
- `just argument-comment-lint`
## Summary
- move skill loading and management into codex-core-skills
- leave codex-core with the thin integration layer and shared wiring
## Testing
- CI
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Co-authored-by: Codex <noreply@openai.com>