Implement rag-search skill for semantic search

Add new skill for semantic search across personal state files and
external documentation using ChromaDB and sentence-transformers.

Components:
- search.py: Main search interface (--index, --top-k flags)
- index_personal.py: Index ~/.claude/state files
- index_docs.py: Index external docs (git repos)
- add_doc_source.py: Manage doc sources
- test_rag.py: Test suite (5/5 passing)

Features:
- Two indexes: personal (116 chunks) and docs (k0s: 846 chunks)
- all-MiniLM-L6-v2 embeddings (384 dimensions)
- ChromaDB persistent storage
- JSON output with ranked results and metadata

Documentation:
- Added to component-registry.json with triggers
- Added /rag command alias
- Updated skills/README.md
- Resolved fc-013 (vector database for agent memory)

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

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

skills/rag-search/references/sources.json

@@ -0,0 +1,14 @@
+{
+  "sources": [
+    {
+      "id": "k0s",
+      "name": "k0s Documentation",
+      "type": "git",
+      "url": "https://github.com/k0sproject/k0s.git",
+      "path": "docs/",
+      "glob": "**/*.md",
+      "version": "main",
+      "last_indexed": "2026-01-04T23:27:40.175671"
+    }
+  ]
+}