refactor: move worktrees from .worktrees/ to .git/pc-worktrees/

Stores worktree directories inside .git/ so they are automatically
ignored by git, removing the need for a .gitignore entry in user repos.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: johannesjo

.gitignore

@@ -2,7 +2,6 @@ node_modules
 dist
 dist-electron
 release
-.worktrees
 .idea
 .claude
 .DS_Store

electron/ipc/git.ts

@@ -189,7 +189,7 @@ export async function createWorktree(
   branchName: string,
   symlinkDirs: string[]
 ): Promise<{ path: string; branch: string }> {
-  const worktreePath = `${repoRoot}/.worktrees/${branchName}`;
+  const worktreePath = `${repoRoot}/.git/pc-worktrees/${branchName}`;
 
   // Try -b first (new branch), fall back to existing branch
   try {
@@ -217,7 +217,7 @@ export async function removeWorktree(
   branchName: string,
   deleteBranch: boolean
 ): Promise<void> {
-  const worktreePath = `${repoRoot}/.worktrees/${branchName}`;
+  const worktreePath = `${repoRoot}/.git/pc-worktrees/${branchName}`;
 
   if (!fs.existsSync(repoRoot)) return;
 

src/components/NewTaskDialog.tsx

@@ -306,7 +306,7 @@ export function NewTaskDialog() {
                   <svg width="11" height="11" viewBox="0 0 16 16" fill="currentColor" style={{ "flex-shrink": "0" }}>
                     <path d="M1.75 1A1.75 1.75 0 0 0 0 2.75v10.5C0 14.216.784 15 1.75 15h12.5A1.75 1.75 0 0 0 16 13.25v-8.5A1.75 1.75 0 0 0 14.25 3H7.5a.25.25 0 0 1-.2-.1l-.9-1.2C6.07 1.26 5.55 1 5 1H1.75Z" />
                   </svg>
-                  {selectedProjectPath()}/.worktrees/{branchPreview()}
+                  {selectedProjectPath()}/.git/pc-worktrees/{branchPreview()}
                 </span>
               </div>
             </Show>