refactor(vault): Phase 3 — metadata convergence

- Backfill `created` frontmatter on 266 active notes (git date or mtime)
- Normalize `status` to 4 values: draft/active/done/archived (11 notes)
  - Active/进行中/needs-review → active
  - archive → archived
  - 待执行/conditional → draft
  - 完成/accepted → done
- Declare clipper boundary: 04_Archive/Inbox-Clippings/** exempt from migration
- Update depth rule: max 3 → max 4 levels (new notes only)
- Add metadata-converge.mjs script for reproducibility

03_Resources/Development/Languages/Python/Better developers Using from X import Y in Python.md

@@ -1,3 +1,6 @@
+---
+created: 2026-01-05
+---
 Title: "\[Better Developers\] Using 'From X Import Y' in Python"
 Author: [[Reuven Lerner]]
 From: 

03_Resources/Development/Languages/Python/Mock Patching.md

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+---
+created: 2026-01-05
+---
 ## Highlights: 
 `Mock.patch `  will intercept import statements identified by a string, and return a Mock instance you can preconfigure using the techniques we discussed above.