refactor(linkedin)!: rename plugin linkedin-thought-leadership → linkedin-studio (v3.0.0)

BREAKING CHANGE: the marketplace slug, the agent namespace
(linkedin-studio:<agent>), and the runtime state-file path
(~/.claude/linkedin-studio.local.md) all change. Reinstall required;
existing state migrated in place (post metrics, streak, history preserved).
The /linkedin:* commands are unchanged — the command namespace is set
per-command in frontmatter and was always independent of the plugin slug.
Functionality is byte-identical to v2.4.0; this release is pure identity.

- dir + manifests: plugins/linkedin-studio + plugin.json + root marketplace.json
- agent namespace updated in commands/newsletter.md (only functional invoker)
- state path updated in 4 hook scripts + topic-rotation prompt + state template
- catch-all skill dir renamed skills/linkedin-studio (5 functional skills unchanged)
- docs + version bump to 3.0.0 across README badge, CHANGELOG, root README/CLAUDE.md
- historical records (CHANGELOG past entries, docs/ build artifacts,
  config-audit v5.0.0 snapshots) intentionally retain the old slug

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

plugins/linkedin-studio/hooks/scripts/stop-reminder.mjs

@@ -0,0 +1,90 @@
+#!/usr/bin/env node
+// stop-reminder.mjs
+// Stop hook for linkedin-studio plugin
+//
+// Only fires if LinkedIn content was worked on (session marker exists).
+// First stop: blocks with reason (Claude processes reminders).
+// Subsequent stops within 60s: allows (prevents infinite loop).
+//
+// Exit codes:
+//   0 - Allow (pass through or second stop)
+//   2 - Not used; uses {"decision": "block"} JSON instead
+
+import { readFileSync, writeFileSync, existsSync, statSync, unlinkSync, mkdirSync } from 'node:fs';
+import { join, dirname } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const pluginRoot = join(__dirname, '..', '..');
+const promptFile = join(pluginRoot, 'hooks', 'prompts', 'state-update-reminder.md');
+
+const sessionDir = '/tmp/linkedin-hooks';
+const sessionMarker = join(sessionDir, 'session-active');
+const lockFile = join(sessionDir, 'stop-hook.lock');
+
+function nowSeconds() {
+  return Date.now() / 1000;
+}
+
+function fileAgeSeconds(filePath) {
+  try {
+    return nowSeconds() - statSync(filePath).mtime.getTime() / 1000;
+  } catch {
+    return Infinity;
+  }
+}
+
+function safeUnlink(filePath) {
+  try { unlinkSync(filePath); } catch { /* ignore */ }
+}
+
+// Read stdin
+let input;
+try {
+  input = JSON.parse(readFileSync(0, 'utf-8'));
+} catch {
+  input = {};
+}
+
+// Infinite loop prevention: if Claude is already continuing from a Stop hook
+if (input.stop_hook_active === true) {
+  process.stdout.write('{}');
+  process.exit(0);
+}
+
+// No session marker = no LinkedIn work done
+if (!existsSync(sessionMarker)) {
+  process.stdout.write('{}');
+  process.exit(0);
+}
+
+// Staleness check: ignore markers older than 12 hours (43200 seconds)
+if (fileAgeSeconds(sessionMarker) > 43200) {
+  safeUnlink(sessionMarker);
+  process.stdout.write('{}');
+  process.exit(0);
+}
+
+// Infinite-loop prevention: lock file within 60 seconds = second stop
+if (existsSync(lockFile)) {
+  if (fileAgeSeconds(lockFile) < 60) {
+    safeUnlink(lockFile);
+    safeUnlink(sessionMarker);
+    process.stdout.write('{}');
+    process.exit(0);
+  }
+  safeUnlink(lockFile);
+}
+
+// First stop: create lock and block with reminder prompt
+mkdirSync(sessionDir, { recursive: true });
+writeFileSync(lockFile, '');
+
+if (!existsSync(promptFile)) {
+  process.stdout.write('{}');
+  process.exit(0);
+}
+
+const promptContent = readFileSync(promptFile, 'utf-8');
+process.stdout.write(JSON.stringify({ decision: 'block', reason: promptContent }));
+process.exit(0);