ci: gate workflows on relevant source paths
- ci.yml: only run on Go/frontend source and lockfiles.
- codeql.yml: scope push/PR triggers to Go and JS/TS sources;
weekly cron still does a full scan.
- release.yml: add matching paths allowlist to pull_request so
doc/workflow-only PRs don't kick off the multi-arch build.
Skips workflow runs on changes to docs, translations, GitHub
configs, and unrelated scripts.