feat: add read-only admin settings

Co-authored-by: Codex <noreply@openai.com>

docs/implementation-status.md

@@ -6,7 +6,7 @@ Update this file before each feature commit.
 | --- | --- | --- | --- | --- |
 | Scaffold | Completed | `fc47967` | `cargo fmt --check`; `cargo test`; `cargo clippy --all-targets --all-features --locked -- -D warnings` | Rust crate, lint policy, pinned TLS-sensitive dependencies, `.gitignore`, and minimal entry points are in place. |
 | API contract docs | Completed | `fc47967` | `cargo fmt --check`; `cargo test`; `cargo clippy --all-targets --all-features --locked -- -D warnings` | `/v1/*` OpenAI-compatible body, `/admin/*` frontend envelope, body codes, camelCase, and request ID policy are documented. |
-| Configuration | Completed | `9ed8579` + `e0680bf` | `cargo test default_config_keeps_only_codex_backend`; `cargo test config_loader_merges_default_local_and_cprs_env_overrides`; full `fmt/test/clippy` before commit | Defines Codex-only config, default/local/env loading, default YAML, and `Arc<AppServices>` state shell. |
+| Configuration | Completed | `9ed8579` + `e0680bf` + `pending` | `cargo test default_config_keeps_only_codex_backend`; `cargo test config_loader_merges_default_local_and_cprs_env_overrides`; full `fmt/test/clippy` before commit | Defines Codex-only config, default/local/env loading, default YAML, `Arc<AppServices>` state shell, `gpt-5.5` default model, and in-scope model/auth/quota/usage/logging settings fields without proxy/Ollama/provider/OpenAI-key knobs. |
 | SQLite storage | Completed | `ffec8b5` + `b0c10f2` | `cargo test sqlite_schema_creates_accounts_and_event_tables`; `cargo test connect_sqlite_creates_parent_directory_for_file_database`; full `fmt/test/clippy` before commit | Creates SQLite WAL connector, parent directory bootstrap, sqlx-managed schema for accounts/API keys/sessions/cookies/fingerprints/events, and event/account indexes. |
 | Admin auth and client API keys | Completed | `24d5799` + `4e0d1e5` | `cargo test client_api_key_has_proxy_prefix_and_verifies_against_hash`; `cargo test admin_password_hash_is_not_a_client_api_key`; `cargo test --test admin_login_route_test`; full `fmt/test/clippy` before commit | Admin passwords use Argon2id, client API keys use `cpr_` prefix plus HMAC-SHA256 with server-side pepper; `/admin/login` issues HttpOnly sessions and rejects client API keys as admin credentials. |
 | Secret encryption | Completed | `105aa58` | `cargo test secret_box_encrypts_and_decrypts_without_storing_plaintext`; full `fmt/test/clippy` before commit | AES-256-GCM `SecretBox` stores upstream secrets as `v1:<nonce>:<ciphertext>` without plaintext. |
@@ -16,7 +16,7 @@ Update this file before each feature commit.
 | Account pool and refresh | Partial | `0f97c5c` + `2f25db8` + `4dc0c9a` | `cargo test account_pool_skips_expired_disabled_banned_and_quota_exhausted_accounts`; `cargo test --test account_pool_scheduling_test`; `cargo test --test account_refresh_test`; full `fmt/test/clippy` before commit | Implements base account status filtering, refresh scheduler semantics, max concurrent slots, stale slot cleanup, least-used/round-robin/sticky strategies, tier priority, quota-cache filtering, Cloudflare cooldown skip, request staggering metadata, preferred account selection, exclude IDs, and capacity summary. Still missing settings-backed scheduling config, SQLite repository integration for pool snapshots/release usage, upstream retry/fallback wiring, and admin account CRUD. |
 | Account repository | Completed | `14fe706` | `cargo test --test account_repository_test`; `cargo fmt --check`; `cargo clippy --all-targets --all-features --locked -- -D warnings`; `cargo test` | Adds encrypted SQLite account token storage, decrypting reads, cursor pagination, status/label updates, release-time usage counter persistence, and refresh-token-preserving token updates. |
 | Translation | Completed | `eff182e` | `cargo test chat_completion_translates_to_codex_response_request`; full `fmt/test/clippy` before commit | Adds OpenAI Chat request types, Codex Responses request type, translation, and OpenAI-compatible error body helper. |
-| HTTP routes | Partial | `ab0ad8f` + `3830b21` + `6179d44` | `cargo test v1_requires_client_api_key_not_admin_cookie`; `cargo test models_route_returns_openai_compatible_codex_model_list`; full `fmt/test/clippy` before commit | Adds Axum router, health route, `/v1/models`, `/v1` unauthorized OpenAI error body, global request-id response header, binary listener, and `gpt-5.5` as the default/test model baseline. Still missing admin auth middleware extraction, account/auth/API-key management routes, settings routes, diagnostics, usage stats, model catalog/detail/refresh routes, and additional Responses routes. |
+| HTTP routes | Partial | `ab0ad8f` + `3830b21` + `6179d44` + `pending` | `cargo test v1_requires_client_api_key_not_admin_cookie`; `cargo test models_route_returns_openai_compatible_codex_model_list`; `cargo test --test admin_settings_route_test`; full `fmt/test/clippy` before commit | Adds Axum router, health route, `/v1/models`, `/v1` unauthorized OpenAI error body, global request-id response header, binary listener, `gpt-5.5` as the default/test model baseline, and read-only `/admin/settings` with admin-session auth and lower camelCase envelope. Still missing admin account/auth/API-key management routes, settings mutation/persistence, diagnostics, usage stats, model catalog/detail/refresh routes, and additional Responses routes. |
 | Admin/frontend response contract | Completed | `1c34ea7` + `b0c10f2` | `cargo test admin_envelope_serializes_lower_camel_case_request_id`; `cargo test admin_logs_reject_missing_admin_session_cookie`; `cargo test v1_response_has_request_id_header_without_admin_body_field`; full `fmt/test/clippy` before commit | Adds reusable admin envelopes with body codes, lower camelCase JSON, paginated list shape, requestId bodies, admin session cookie enforcement, and keeps `/v1/*` OpenAI-compatible. |
 | HTTP auth boundary | Completed | `cec4607` | `cargo test --test http_auth_test`; `cargo test --test routes_responses_test`; `cargo test --test admin_logs_route_test`; `cargo fmt --check`; `cargo clippy --all-targets --all-features --locked -- -D warnings`; `cargo test` | Adds a real `src/http/auth.rs` boundary for client API key and admin session cookie parsing. `/v1/*` accepts only `Bearer cpr_...`, admin session parsing ignores client API keys, and route handlers no longer own ad hoc credential parsing. |
 | Upstream lifecycle | Partial | `88cad87` + `225fbff` | `cargo test responses_route_rejects_non_codex_provider_models`; `cargo test v1_requires_client_api_key_not_admin_cookie`; `cargo test --test codex_sse_usage_test`; full `fmt/test/clippy` before commit | `/v1` currently enforces client API key shape, rejects non-Codex provider models, returns OpenAI-compatible errors, and includes reusable SSE/usage helpers. It does not yet acquire accounts, forward to Codex, replay/capture Cookies, stream/collect upstream responses, capture rate-limit headers, retry across accounts, record usage, or preserve previous-response/session affinity. |