fix: resolve CI failures on main — lint, hooks validator, and test alignment

- Fix MD012 trailing blank lines in commands/projects.md and commands/promote.md
- Fix MD050 strong-style in continuous-learning-v2 (escape __tests__ as inline code)
- Extract doc-file-warning hook to standalone script to fix hooks validator regex parsing
- Update session-end test to match #317 behavior (always update summary content)
- Allow shell script hooks in integration test format validation

All 992 tests passing.

scripts/hooks/doc-file-warning.js

@@ -0,0 +1,24 @@
+/**
+ * Doc file warning hook (PreToolUse - Write)
+ * Warns about non-standard documentation files.
+ * Exit code 0 always (warns only, never blocks).
+ */
+
+let data = '';
+process.stdin.on('data', c => data += c);
+process.stdin.on('end', () => {
+  try {
+    const input = JSON.parse(data);
+    const filePath = input.tool_input?.file_path || '';
+
+    if (/\.(md|txt)$/.test(filePath) &&
+        !/(README|CLAUDE|AGENTS|CONTRIBUTING|CHANGELOG|LICENSE|SKILL)\.md$/i.test(filePath) &&
+        !/\.claude[\/\\]plans[\/\\]/.test(filePath) &&
+        !/(^|[\/\\])(docs|skills)[\/\\]/.test(filePath)) {
+      console.error('[Hook] WARNING: Non-standard documentation file detected');
+      console.error('[Hook] File: ' + filePath);
+      console.error('[Hook] Consider consolidating into README.md or docs/ directory');
+    }
+  } catch { /* ignore parse errors */ }
+  console.log(data);
+});