chore: track claude skills, tools, templates, reference code and research-wiki

- Add all claude skills (brainstorming, commit, debugging, TDD, etc.)
- Add claude hooks (pre-commit-guard, post-edit-quality)
- Add research templates (experiment plan, research brief, etc.)
- Add claude tools (arxiv/semantic_scholar/openalex fetch, wiki, exa)
- Add TRM4 reference implementation as algorithm fidelity baseline
- Add research-wiki content (plans, index, graph, query_pack)
- Update .gitignore to exclude .graphify_version runtime state

.claude/skills/graphify/references/add-watch.md

@@ -0,0 +1,56 @@
+# graphify reference: add a URL and watch a folder
+
+Load this when the user ran `/graphify add <url>` or passed `--watch`. Neither is part of the default build.
+
+## For /graphify add
+
+Fetch a URL and add it to the corpus, then update the graph.
+
+```bash
+$(cat graphify-out/.graphify_python) -c "
+import sys
+from graphify.ingest import ingest
+from pathlib import Path
+
+try:
+    out = ingest('URL', Path('./raw'), author='AUTHOR', contributor='CONTRIBUTOR')
+    print(f'Saved to {out}')
+except ValueError as e:
+    print(f'error: {e}', file=sys.stderr)
+    sys.exit(1)
+except RuntimeError as e:
+    print(f'error: {e}', file=sys.stderr)
+    sys.exit(1)
+"
+```
+
+Replace `URL` with the actual URL, `AUTHOR` with the user's name if provided, `CONTRIBUTOR` likewise. If the command exits with an error, tell the user what went wrong - do not silently continue. After a successful save, automatically run the `--update` pipeline on `./raw` to merge the new file into the existing graph.
+
+Supported URL types (auto-detected):
+- YouTube / any video URL → audio downloaded via yt-dlp, transcribed to `.txt` on next run (requires `pip install 'graphifyy[video]'`)
+- Twitter/X → fetched via oEmbed, saved as `.md` with tweet text and author
+- arXiv → abstract + metadata saved as `.md`
+- PDF → downloaded as `.pdf`
+- Images (.png/.jpg/.webp) → downloaded, Claude vision extracts on next run
+- Any webpage → converted to markdown via html2text
+
+---
+
+## For --watch
+
+Start a background watcher that monitors a folder and auto-updates the graph when files change.
+
+```bash
+python3 -m graphify.watch INPUT_PATH --debounce 3
+```
+
+Replace INPUT_PATH with the folder to watch. Behavior depends on what changed:
+
+- **Code files only (.py, .ts, .go, etc.):** re-runs AST extraction + rebuild + cluster immediately, no LLM needed. `graph.json` and `GRAPH_REPORT.md` are updated automatically.
+- **Docs, papers, or images:** writes a `graphify-out/needs_update` flag and prints a notification to run `/graphify --update` (LLM semantic re-extraction required).
+
+Debounce (default 3s): waits until file activity stops before triggering, so a wave of parallel agent writes doesn't trigger a rebuild per file.
+
+Press Ctrl+C to stop.
+
+For agentic workflows: run `--watch` in a background terminal. Code changes from agent waves are picked up automatically between waves. If agents are also writing docs or notes, you'll need a manual `/graphify --update` after those waves.