Tighten JSR ref cleanup

Use a wildcard ignore pattern for generated JSR reference cache files so new
package-specific caches do not require separate ignore entries.

Trim pnpm-lock.yaml so the dependency update only records the
markdown-it-jsr-ref version change and avoids unrelated transitive churn.

#723 (comment)
#723 (comment)

Assisted-by: Codex:gpt-5.5

Author: dahlia

docs/.gitignore

@@ -1,9 +1,5 @@
 .jsr-cache.json
-.jsr-debugger-cache.json
-.jsr-testing-cache.json
-.jsr-vocab-cache.json
-.jsr-vocab-runtime-cache.json
-.jsr-webfinger-cache.json
+.jsr-*-cache.json
 .vitepress/cache/
 .vitepress/dist/
 node_modules/