sync: bug fixes + eval system from private repo

- Fix chunk_status: pass chunk_status/chunk/metadata to context builder
- Fix vector search: scope by node_id BEFORE similarity search
- Add eval logging system (RAH_EVALS_LOG=1)
- Add eval dashboard at /evals
- Add vitest for testing

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

tests/evals/scenarios/dimension-lifecycle.ts

@@ -0,0 +1,15 @@
+import { Scenario } from '../types';
+
+export const scenario: Scenario = {
+  id: 'dimension-lifecycle',
+  name: 'Dimension lifecycle (create/update/lock/unlock)',
+  description: 'Create a dimension, update its description, lock it, then unlock it.',
+  tools: ['createDimension', 'updateDimension', 'lockDimension', 'unlockDimension'],
+  input: {
+    message: 'Create a dimension named "eval-dim" with description "temporary eval dimension", then update the description to "eval dimension updated", then lock it, then unlock it.',
+  },
+  expect: {
+    toolsCalledSoft: ['createDimension', 'updateDimension', 'lockDimension', 'unlockDimension'],
+    responseContainsSoft: ['eval-dim'],
+  },
+};