feat(main): 实现字幕引擎控制功能

- 新增字幕引擎启动和停止功能
- 实现控制窗口的字幕引擎状态显示
- 优化字幕日志的发送逻辑
- 重构子进程相关代码

src/main/utils/engine.ts

@@ -0,0 +1,79 @@
+import { spawn } from 'child_process'
+import { app } from 'electron'
+import path from 'path'
+import { addCaptionLog, controls } from './config'
+
+export class CaptionEngine { 
+    appPath: string = ''
+    command: string[] = []
+    process: any | undefined
+
+    private getApp() {
+        if(controls.customized && controls.customizedCommand && controls.customizedApp){
+            this.appPath = controls.customizedApp
+            this.command = [ controls.customizedCommand ]
+        }
+        else if(controls.engine === 'gummy'){
+            this.appPath = path.join(
+                app.getAppPath(),
+                'python-subprocess', 'subenv', 'Scripts', 'python.exe'
+            )
+            this.command = []
+            this.command.push(path.join(
+                app.getAppPath(),
+                'python-subprocess', 'main.py'
+            ))
+            this.command.push('-s', controls.sourceLang)
+            this.command.push('-t', controls.targetLang)
+
+            console.log(this.appPath)
+            console.log(this.command)
+        }
+    }
+
+    public start() { 
+        if (this.process) {
+            this.stop();
+        }
+        this.getApp()
+        this.process = spawn(this.appPath, this.command)
+        controls.engineEnabled = true
+
+        console.log('[INFO] Caption Engine Started: ', {
+            appPath: this.appPath,
+            command: this.command
+        })
+
+        this.process.stdout.on('data', (data) => {
+            const lines = data.toString().split('\n');
+            lines.forEach( (line: string) => {
+                if (line.trim()) {
+                    try {
+                        const caption = JSON.parse(line);
+                        addCaptionLog(caption);
+                    } catch (e) {
+                        console.error('Error parsing JSON:', e);
+                    }
+                }
+            });
+        });
+        
+        this.process.stderr.on('data', (data) => {
+            console.error(`Python Error: ${data}`);
+        });
+        
+        this.process.on('close', (code: any) => {
+            console.log(`Python process exited with code ${code}`);
+            this.process = undefined;
+        });
+    }
+
+    public stop() {
+        if (this.process) {
+            this.process.kill();
+            this.process = undefined;
+            controls.engineEnabled = false;
+            console.log('[INFO] Caption engine process stopped');
+        }
+    }
+}