track the name agents read, so a clone documents itself

LLM.md is the source and stays the source; CLAUDE.md is a symlink to it, so there is
one file and it cannot drift from itself. What changes is that the link is committed
rather than left for each checkout to recreate.

Left untracked, the doc was conditional on a step outside the repo: a fresh clone had
no CLAUDE.md, nothing loaded LLM.md, and an agent worked here having never read what
this repo already explains. 516 repos in the estate already track theirs; this is the
rest agreeing with them.

.gitignore

@@ -36,6 +36,5 @@ Thumbs.db
 *.tsbuildinfo
 next-env.d.ts
 AGENTS.md
-CLAUDE.md
 GEMINI.md
 QWEN.md

CLAUDE.md

@@ -0,0 +1 @@
+LLM.md