feat: Superpowers for Copilot Chat VS Code extension v1.0.0

- @superpowers chat participant with 14 skill slash commands
- Bundled SKILL.md files for all Superpowers skills
- Custom skill support via ~/.copilot/skills/superpowers/
- Live file watcher — custom skills reload without restart
- TypeScript source: skillLoader, participant, watcher, extension

Skills: brainstorming, tdd, debug, plan, execute, subagent,
parallel, review, receive-review, verify, worktree, finish,
write-skill, superpowers

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

src/watcher.ts

@@ -0,0 +1,29 @@
+import * as vscode from 'vscode';
+import { getCustomSkillsDir } from './skillLoader';
+
+/** Start watching the custom skills directory for changes.
+ *  Calls onReload whenever a SKILL.md is added, changed, or deleted.
+ *  Returns a Disposable to stop watching. */
+export function startWatcher(
+  context: vscode.ExtensionContext,
+  onReload: () => void
+): vscode.Disposable {
+  const customDir = getCustomSkillsDir();
+  const pattern = new vscode.RelativePattern(vscode.Uri.file(customDir), '**/SKILL.md');
+  const watcher = vscode.workspace.createFileSystemWatcher(pattern);
+
+  let debounceTimer: ReturnType<typeof setTimeout> | undefined;
+
+  const triggerReload = () => {
+    if (debounceTimer) {
+      clearTimeout(debounceTimer);
+    }
+    debounceTimer = setTimeout(onReload, 500);
+  };
+
+  watcher.onDidCreate(triggerReload, null, context.subscriptions);
+  watcher.onDidChange(triggerReload, null, context.subscriptions);
+  watcher.onDidDelete(triggerReload, null, context.subscriptions);
+
+  return watcher;
+}