revert(codex): remove Luna Reserve fallback (#1780)

Revert 8357da0a9d and its later shared-runtime integration.

Remove automatic model fallback, account usage polling, and the related UI, protocol fields, tests, and documentation without adding replacement quota handling.

Keep generic model pagination and method probing required by the current shared-session architecture. Cover idle sessions staying online without usage polling or agent-state churn.

cli/src/codex/codexAppServerClient.ts

@@ -5,7 +5,6 @@ import { logger } from '@/ui/logger';
 import { JsonLineParser } from '@/utils/jsonLineParser';
 import { killProcessByChildProcess } from '@/utils/process';
 import type {
-    ThreadSettingsUpdateParams,
     CollaborationModeListResponse,
     InitializeParams,
     InitializeResponse,
@@ -356,14 +355,6 @@ export class CodexAppServerClient extends JsonLineParser {
         return response as ConfigReadResponse;
     }
 
-    async readAccountRateLimits(supportsLunaReserve = false): Promise<unknown> {
-        return this.sendRequest('account/rateLimits/read', supportsLunaReserve ? { supportsLunaReserve: true } : null, { timeoutMs: 30_000 });
-    }
-
-    async updateThreadSettings(params: ThreadSettingsUpdateParams): Promise<void> {
-        await this.sendRequest('thread/settings/update', params, { timeoutMs: 30_000 });
-    }
-
     async listModels(params?: ModelListParams): Promise<ModelListResponse> {
         const response = await this.sendRequest('model/list', params ?? {}, {
             timeoutMs: 30_000