## Why
`Permissions` should not store a separate `PermissionProfile` that can
drift from the constrained `SandboxPolicy` and network settings. The
active profile needs to be derived from the same constrained values that
already honor `requirements.toml`.
## What changed
This adds derivation of the active `PermissionProfile` from the
constrained runtime permission settings and exposes that derived value
through config snapshots and thread state. The app-server can then
report the active profile without introducing a second source of truth.
## Verification
- `cargo test -p codex-core --test all permissions_messages --
--nocapture`
- `cargo test -p codex-core --test all request_permissions --
--nocapture`
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/18277).
* #18288
* #18287
* #18286
* #18285
* #18284
* #18283
* #18282
* #18281
* #18280
* #18279
* #18278
* __->__ #18277
## Summary
The Bedrock Mantle SigV4 auth provider currently looks like it can
lazily load `AwsAuthContext`, but the provider is only constructed after
`resolve_auth_method` has already loaded that context. Because
`with_context` always pre-populates the `OnceCell`, the
`get_or_try_init` fallback is unused in normal operation and makes the
provider lifecycle harder to reason about.
This change removes that dead lazy-loading path and makes the actual
behavior explicit:
- `BedrockAuthMethod::AwsSdkAuth` carries only the resolved
`AwsAuthContext`.
- `BedrockMantleSigV4AuthProvider` stores the resolved context directly.
- request signing uses the stored context without going through
`OnceCell`.
The existing eager AWS auth resolution behavior is unchanged; this is a
simplification of the provider state, not a behavior change.
## Testing
- `cargo shear`
- `cargo test -p codex-model-provider`
- `just bazel-lock-check`
## Summary
- Keep the guardian policy installed as guardian base instructions.
- Clear inherited parent `developer_instructions` for guardian review
sessions.
- Update guardian config tests to assert developer instructions are
cleared and policy text is sourced from base instructions.
## Why
Guardian review sessions are intended to run under an isolated guardian
policy. Because the guardian config is cloned from the parent config,
inherited custom or managed developer instructions could otherwise
remain active and conflict with guardian review behavior.
## Validation
- `just fmt`
- `cargo test -p codex-core guardian_review_session_config`
Co-authored-by: Codex <noreply@openai.com>