chore: polish for FOL contract delivery (CHANGELOG, CLI guardrails, metadata)

- Update CHANGELOG.md for 1.1.0 (date, refactoring, repository fixes)
- Add overwrite guardrails to imhotep-cli init — skips existing files
- Add bugs/homepage/keywords metadata to 5 public packages
- Mark imhotep-bench and imhotep-fixtures as private packages
- Add selector field to SourceReference interface (core types)
- Remove 7  casts from check-all.ts (folAst.position, cardinality results)
- Generate package-lock.json for reproducible installs

packages/imhotep-playwright/src/public.test.ts

@@ -984,7 +984,7 @@ describe('Selector Cardinality Contracts (P2.1)', () => {
     if (cardClause) {
       assert.strictEqual(cardClause.metrics.observedCount, 0)
       assert.strictEqual(cardClause.metrics.expectedCount, 1)
-      assert.strictEqual(cardClause.metrics.selector, '.does-not-exist')
+      assert.strictEqual(cardClause.sourceRef?.selector, '.does-not-exist')
     }
   })
 })