refactor: 全面清理死代码 — 删除 348 行无用代码

删除文件:
- training-export.ts: 训练数据导出（零引用，UI 已移除）

删除函数:
- workspace.ts: isProcessAlive, getActiveProcessCount, execWorkspaceCommand, terminateWorkspaceCommand
- sqlite.ts: deleteMessagesBySession, getSkill, closeDatabase
- tool-registry.ts: isToolEnabled
- cron-manager.ts: clearAllTimers
- workspace-panel.ts: setOnToolTerminated, setWorkspaceDirPath

删除 UI:
- index.html: 训练数据导出按钮及说明
- settings-modal.ts: 训练数据导出事件绑定

src/renderer/services/cron-manager.ts

@@ -183,12 +183,3 @@ export async function restoreCronTasks(): Promise<void> {
     logInfo(`定时任务已恢复: ${scheduled} 个任务`);
   }
 }
-
-/**
- * 清理所有定时器（应用退出时调用）
- */
-export function clearAllTimers(): void {
-  for (const [id] of activeTimers) {
-    clearTimer(id);
-  }
-}

src/renderer/services/tool-registry.ts

@@ -572,9 +572,6 @@ export function setToolEnabled(toolName: string, enabled: boolean): void {
   else enabledTools.delete(toolName);
 }
 
-export function isToolEnabled(toolName: string): boolean {
-  return enabledTools.has(toolName);
-}
 
 export function getEnabledToolDefinitions(): ToolDefinition[] {
   const builtIn = TOOL_DEFINITIONS.filter(def => enabledTools.has(def.function.name));

src/renderer/services/training-export.ts

@@ -1,130 +0,0 @@
-/**
- * TrainingExport - 训练数据导出 (v5.0)
- * 将 Agent 执行轨迹转换为 SFT 训练数据格式
- */
-
-import { state, KEYS } from '../state/state.js';
-import { logInfo, logSuccess, logError } from './log-service.js';
-
-interface SFTRecord {
-  instruction: string;
-  input: string;
-  output: string;
-  tools?: Array<{ name: string; arguments: Record<string, unknown> }>;
-  observations?: string[];
-  metadata?: {
-    session_id: string;
-    session_title: string;
-    timestamp: number;
-    model: string;
-    eval_count?: number;
-    total_duration?: number;
-  };
-}
-
-/**
- * 导出所有会话的训练数据
- * 从 traces + messages 中提取成功的工具调用链
- */
-export async function exportTrainingData(): Promise<string | null> {
-  const bridge = (window as any).metonaDesktop;
-  if (!bridge?.db) return null;
-
-  try {
-    const sessions = await bridge.db.getAllSessions();
-    const records: SFTRecord[] = [];
-
-    for (const session of sessions) {
-      const messages = await bridge.db.getMessages(session.id);
-      const traces = await bridge.db.getTraces(session.id);
-
-      // 遍历消息对（user → assistant）
-      for (let i = 0; i < messages.length - 1; i++) {
-        const userMsg = messages[i];
-        const asstMsg = messages[i + 1];
-
-        if (userMsg.role !== 'user' || asstMsg.role !== 'assistant') continue;
-        if (!userMsg.content || !asstMsg.content) continue;
-
-        // 解析工具调用
-        let tools: Array<{ name: string; arguments: Record<string, unknown> }> | undefined;
-        let observations: string[] | undefined;
-
-        if (asstMsg.tool_calls) {
-          try {
-            const toolCalls = JSON.parse(asstMsg.tool_calls);
-            if (Array.isArray(toolCalls) && toolCalls.length > 0) {
-              tools = toolCalls.map((tc: any) => ({
-                name: tc.name || tc.function?.name || 'unknown',
-                arguments: tc.arguments || tc.function?.arguments || {}
-              }));
-            }
-          } catch { /* ignore */ }
-        }
-
-        // 从 traces 中提取 observation
-        const sessionTraces = traces.filter(t =>
-          t.created_at >= userMsg.created_at && t.created_at <= asstMsg.created_at
-        );
-        if (sessionTraces.length > 0) {
-          observations = sessionTraces.map(t => t.observation || '').filter(Boolean);
-        }
-
-        records.push({
-          instruction: userMsg.content,
-          input: '',
-          output: asstMsg.content,
-          ...(tools && { tools }),
-          ...(observations?.length && { observations }),
-          metadata: {
-            session_id: session.id,
-            session_title: session.title,
-            timestamp: userMsg.created_at,
-            model: session.model,
-            ...(asstMsg.eval_count && { eval_count: asstMsg.eval_count }),
-            ...(asstMsg.total_duration && { total_duration: asstMsg.total_duration })
-          }
-        });
-
-        i++; // 跳过 assistant 消息
-      }
-    }
-
-    if (records.length === 0) {
-      logInfo('训练数据导出: 无可导出数据');
-      return null;
-    }
-
-    logSuccess(`训练数据导出完成: ${records.length} 条记录`);
-    return records.map(r => JSON.stringify(r)).join('\n');
-  } catch (err) {
-    logError('训练数据导出失败', (err as Error).message);
-    return null;
-  }
-}
-
-/**
- * 保存训练数据到文件
- */
-export async function saveTrainingData(): Promise<boolean> {
-  const bridge = (window as any).metonaDesktop;
-  if (!bridge?.dialog?.saveFile) return false;
-
-  const data = await exportTrainingData();
-  if (!data) return false;
-
-  try {
-    const filePath = await bridge.dialog.saveFile({
-      defaultPath: `metona-training-data-${new Date().toISOString().slice(0, 10)}.jsonl`,
-      filters: [{ name: 'JSONL', extensions: ['jsonl'] }, { name: 'JSON', extensions: ['json'] }]
-    });
-    if (!filePath) return false;
-
-    await bridge.fs.writeFile(filePath, data);
-    logSuccess(`训练数据已保存: ${filePath}`);
-    return true;
-  } catch (err) {
-    logError('保存训练数据失败', (err as Error).message);
-    return false;
-  }
-}