feat: cross-platform support with Node.js scripts

- Rewrite all bash hooks to Node.js for Windows/macOS/Linux compatibility
- Add package manager auto-detection (npm, pnpm, yarn, bun)
- Add scripts/lib/ with cross-platform utilities
- Add /setup-pm command for package manager configuration
- Add comprehensive test suite (62 tests)

Co-authored-by: zerx-lab

scripts/hooks/pre-compact.js

@@ -0,0 +1,48 @@
+#!/usr/bin/env node
+/**
+ * PreCompact Hook - Save state before context compaction
+ *
+ * Cross-platform (Windows, macOS, Linux)
+ *
+ * Runs before Claude compacts context, giving you a chance to
+ * preserve important state that might get lost in summarization.
+ */
+
+const path = require('path');
+const {
+  getSessionsDir,
+  getDateTimeString,
+  getTimeString,
+  findFiles,
+  ensureDir,
+  appendFile,
+  log
+} = require('../lib/utils');
+
+async function main() {
+  const sessionsDir = getSessionsDir();
+  const compactionLog = path.join(sessionsDir, 'compaction-log.txt');
+
+  ensureDir(sessionsDir);
+
+  // Log compaction event with timestamp
+  const timestamp = getDateTimeString();
+  appendFile(compactionLog, `[${timestamp}] Context compaction triggered\n`);
+
+  // If there's an active session file, note the compaction
+  const sessions = findFiles(sessionsDir, '*.tmp');
+
+  if (sessions.length > 0) {
+    const activeSession = sessions[0].path;
+    const timeStr = getTimeString();
+    appendFile(activeSession, `\n---\n**[Compaction occurred at ${timeStr}]** - Context was summarized\n`);
+  }
+
+  log('[PreCompact] State saved before compaction');
+  process.exit(0);
+}
+
+main().catch(err => {
+  console.error('[PreCompact] Error:', err.message);
+  process.exit(0);
+});