Enforce managed provider requirements on existing app-server threads (#44944)

## Why

Existing threads retain their model provider configuration, which can stop matching managed requirements after those requirements change.

## What changed

- Check retained providers against current managed `model_provider` and `model_providers` requirements before turn start/steer, review, compaction, manual queue start, and active goal updates. Reject requests when requirements cannot be loaded or no longer match; provider mismatches prompt users to restart Codex.
- Load managed requirements independently of user, project, system defaults, and thread configuration, and resolve Bedrock provider overrides before comparison.
- Keep interrupt, realtime stop, and goal pause/clear available. Realtime connections use separate routing and are outside these checks.
- Make detached reviews inherit their parent thread's configuration.

## Testing

Add unit and integration coverage for provider selection and definition changes, Bedrock overrides, requirement load failures, unchanged queue and goal state after rejection, and continued operation after local configuration changes. Extend detached review coverage to verify inheritance of the parent's provider route.

GitOrigin-RevId: 21abf08ad2bcc2ea4698209fa33a17485eed4740

codex-rs/app-server/Cargo.toml

@@ -77,6 +77,7 @@ codex-memories-write = { workspace = true }
 codex-mcp = { workspace = true }
 codex-mcp-extension = { workspace = true }
 codex-model-provider = { workspace = true }
+codex-model-provider-info = { workspace = true }
 codex-models-manager = { workspace = true }
 codex-protocol = { workspace = true }
 codex-queue-extension = { workspace = true }
@@ -131,7 +132,6 @@ axum = { workspace = true, default-features = false, features = [
     "tokio",
 ] }
 base64 = { workspace = true }
-codex-model-provider-info = { workspace = true }
 codex-utils-cargo-bin = { workspace = true }
 core_test_support = { workspace = true }
 flate2 = { workspace = true }