fix: replace 'as any' with proper type assertion for git tool args

The git tool handler in ipc.ts was using 'args as any' to bypass type
checking. Replaced with the explicit typed params interface matching
handleGit's signature to maintain type safety.

src/main/ipc.ts

@@ -187,7 +187,7 @@ export async function setupIPC(): Promise<void> {
         case 'diff_files':         result = await handleDiffFiles(args as { file1: string; file2: string; context_lines?: number }); break;
         case 'replace_in_files':   result = await handleReplaceInFiles(args as { path: string; glob: string; old_text: string; new_text: string }); break;
         case 'read_multiple_files':result = await handleReadMultipleFiles(args as { paths: string[]; max_chars_per_file?: number }); break;
-        case 'git':                result = await handleGit(args as any); break;
+        case 'git':                result = await handleGit(args as { action: string; path?: string; files?: string[]; message?: string; branch?: string; remote?: string; remote_url?: string; count?: number; all?: boolean; staged?: boolean; new_branch?: boolean; delete_branch?: boolean; force?: boolean; url?: string }); break;
         case 'compress':           result = await handleCompress(args as { action: string; path: string; destination?: string; format?: string }); break;
         // v5.0 Browser 控制
         case 'browser_open':       result = await browserOpen(args.url as string); break;