feat(frontend): implement comprehensive API Settings Management Interface

Implement a complete API Management Interface for React frontend with split-
panel layout, migrating all features from legacy JS frontend.

New Features:
- API Settings page with 5 tabs: Providers, Endpoints, Cache, Model Pools, CLI Settings
- Provider Management: CRUD operations, multi-key rotation, health checks, test connection
- Endpoint Management: CRUD operations, cache strategy configuration, enable/disable toggle
- Cache Settings: Global configuration, statistics display, clear cache functionality
- Model Pool Management: CRUD operations, auto-discovery feature, provider exclusion
- CLI Settings Management: Provider-based and Direct modes, full CRUD support
- Multi-Key Settings Modal: Manage API keys with rotation strategies and weights
- Manage Models Modal: View and manage models per provider (LLM and Embedding)
- Sync to CodexLens: Integration handler for provider configuration sync

Technical Implementation:
- Created 12 new React components in components/api-settings/
- Extended lib/api.ts with 460+ lines of API client functions
- Created hooks/useApiSettings.ts with 772 lines of TanStack Query hooks
- Added RadioGroup UI component for form selections
- Implemented unified error handling with useNotifications across all operations
- Complete i18n support (500+ keys in English and Chinese)
- Route integration (/api-settings) and sidebar navigation

Code Quality:
- All acceptance criteria from plan.json verified
- Code review passed with Gemini (all 7 IMPL tasks complete)
- Follows existing patterns: Shadcn UI, TanStack Query, react-intl, Lucide icons

ccw/src/tools/cli-executor-core.ts

@@ -345,6 +345,45 @@ import {
 const BUILTIN_CLI_TOOLS = ['gemini', 'qwen', 'codex', 'opencode', 'claude'] as const;
 type BuiltinCliTool = typeof BUILTIN_CLI_TOOLS[number];
 
+/**
+ * Transaction ID type for concurrent session disambiguation
+ * Format: ccw-tx-${conversationId}-${timestamp}
+ */
+export type TransactionId = string;
+
+/**
+ * Generate a unique transaction ID for the current execution
+ * @param conversationId - CCW conversation ID
+ * @returns Transaction ID in format: ccw-tx-${conversationId}-${uniquePart}
+ */
+export function generateTransactionId(conversationId: string): TransactionId {
+  // Use crypto.randomUUID() if available, otherwise use timestamp + random
+  const uniquePart = typeof crypto !== 'undefined' && crypto.randomUUID
+    ? crypto.randomUUID().slice(0, 8)
+    : `${Date.now()}-${Math.random().toString(36).slice(2, 9)}`;
+  return `ccw-tx-${conversationId}-${uniquePart}`;
+}
+
+/**
+ * Inject transaction ID into user prompt
+ * @param prompt - Original user prompt
+ * @param txId - Transaction ID to inject
+ * @returns Prompt with transaction ID injected at the start
+ */
+export function injectTransactionId(prompt: string, txId: TransactionId): string {
+  return `[CCW-TX-ID: ${txId}]\n\n${prompt}`;
+}
+
+/**
+ * Extract transaction ID from prompt
+ * @param prompt - Prompt that may contain transaction ID
+ * @returns Transaction ID if found, null otherwise
+ */
+export function extractTransactionId(prompt: string): TransactionId | null {
+  const match = prompt.match(/\[CCW-TX-ID:\s+([^\]]+)\]/);
+  return match ? match[1] : null;
+}
+
 // Define Zod schema for validation
 // tool accepts built-in tools or custom endpoint IDs (CLI封装)
 const ParamsSchema = z.object({
@@ -788,6 +827,17 @@ async function executeCliTool(
         timestamp: new Date().toISOString()
       });
     }
+
+    // Info message for Codex TTY limitation
+    if (tool === 'codex' && !supportsNativeResume(tool) && resumeDecision.strategy !== 'native') {
+      if (onOutput) {
+        onOutput({
+          type: 'stderr',
+          content: '[ccw] Using prompt-concat mode for Codex (Codex TTY limitation for native resume)\n',
+          timestamp: new Date().toISOString()
+        });
+      }
+    }
   }
 
   // Use configured primary model if no explicit model provided