fix: broken tests and stale .env.example

- Fix container-runner bug: stopContainer() returns void but was
  passed to exec() as a command string. Replace with direct call
  and try/catch.
- Mock container-runtime in tests so they don't need Docker running.
- Increase claw-skill test timeout to handle slower python startup.
- Clear .env.example (telegram token was added by mistake).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/claw-skill.test.ts

@@ -6,7 +6,7 @@ import { spawnSync } from 'child_process';
 import { describe, expect, it } from 'vitest';
 
 describe('claw skill script', () => {
-  it('exits zero after successful structured output even if the runtime is terminated', () => {
+  it('exits zero after successful structured output even if the runtime is terminated', { timeout: 20000 }, () => {
     const tempDir = fs.mkdtempSync(path.join(os.tmpdir(), 'claw-skill-test-'));
     const binDir = path.join(tempDir, 'bin');
     fs.mkdirSync(binDir, { recursive: true });