feat: add one-click git sync button

Combine fetch, pull with rebase, and push into one sync action
Keep remote dropdown focused on safe fetch actions
Block sync when uncommitted changes would conflict with rebase

packages/vscode/src/gitService.ts

@@ -2360,11 +2360,11 @@ export async function gitPush(
  */
 export async function gitPull(
   directory: string,
-  options?: { remote?: string; branch?: string }
+  options?: { remote?: string; branch?: string; rebase?: boolean }
 ): Promise<{ success: boolean; summary: { changes: number; insertions: number; deletions: number }; files: string[]; insertions: number; deletions: number }> {
   const repo = await getRepository(directory);
   
-  if (repo) {
+  if (repo && options?.rebase !== true) {
     try {
       await repo.pull();
       return {
@@ -2381,10 +2381,14 @@ export async function gitPull(
 
   // Fallback to raw git
   const args = ['pull'];
+  if (options?.rebase === true) args.push('--rebase');
   if (options?.remote) args.push(options.remote);
   if (options?.branch) args.push(options.branch);
 
   const result = await execGit(args, directory);
+  if (result.exitCode !== 0) {
+    throw new Error(result.stderr.trim() || result.stdout.trim() || 'Failed to pull from remote');
+  }
   
   return {
     success: result.exitCode === 0,