chore: drop stragglers from the regtest-tooling removal

.gitignore still carried rules for docker/**/data/ and docker/.state/ —
paths that no longer exist — under a now-empty "# Docker" header. The
docs skill's example sync report named LIGHTNING_PUB_URL as its sample
env var; swapped for a variable that exists.

.claude/skills/docs.md

@@ -175,7 +175,7 @@ From git commits since last release:
 
 ### Suggested Updates
 1. `api/clink.md:45` - Add `timeout` parameter to createOffer
-2. `guides/development.md` - Add LIGHTNING_PUB_URL env var
+2. `guides/development.md` - Add VITE_BITSPIRE_CASSETTES env var
 
 ### Missing Documentation
 - `packages/cashu/src/wallet.ts` - No API docs

.gitignore

@@ -59,10 +59,6 @@ apps/machine/src/services/*.js
 .direnv/
 .pre-commit-config.yaml
 
-# Docker
-docker/**/data/
-docker/.state/
-
 # Nix build outputs
 result
 result-*