README: add the ingest recipe, fix the halogen repo link

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EvxzSKi1zR395wvYXUenVE

README.md

@@ -14,7 +14,8 @@ a retrieval store, not in a skill.
 
 - **Anything specific to one machine or one project.** A local Gitea's branch-naming rule, this
   box's PR checklist — that's instance-bound and belongs in that project's own KB corpus instead
-  (`kb-engineering` for [halogen](https://pi5-16.local/mikkeli/halogen-workstation-roadmap)).
+  (the `engineering` corpus, for
+  [halogen](https://git.novoyuuparosk.org/mikkeli/halogen-workstation-roadmap)).
 - **Short, prescriptive procedures achievable within a context window or two.** That's a skill, not
   a handbook — it gets loaded, not retrieved. See `skills/` in the halogen-workstation-roadmap repo
   for the sibling convention.
@@ -27,7 +28,23 @@ a retrieval store, not in a skill.
 One markdown file per topic at the repo root. Each file should stand as a single admittable
 document — the same shape a human vouches for at KB admission time.
 
+## Ingesting a handbook
+
+Markdown needs no conversion and no extraction verifier — admit it straight from this repo:
+
+```bash
+index.py admit ~/dev/handbooks/git-operations.md --corpus engineering \
+  --vouch mikkeli --title 'Git operations' --collection dev-practice
+```
+
+Without `--title` the document is titled by its filename, which is what a retrieval hit then shows.
+`--collection` is a flat cluster tag; getting it wrong costs recall and nothing else.
+
+⚠ **Editing a file here does not update the corpus.** Re-admission is deliberate, because the vouch
+is a claim about a specific version of a document.
+
 ## Status
 
 Started 2026-08-21. First handbook, `git-operations.md`, composed 2026-08-21 – 2026-08-22: branching,
 committing, merging vs. rebasing, reverting and undoing, remotes and collaboration, tags and releases.
+Confirmed ingestible 2026-08-22 — 30 chunks, heading paths intact, retrieved correctly.