* fix(editor): add missing @chevrotain/regexp-to-ast dependency
langium (mermaid → @mermaid-js/parser → langium) imports
@chevrotain/regexp-to-ast directly but doesn't declare it as a
dependency. Under pnpm's strict node_modules layout the bare import
fails during both Vite dev and production builds.
Adding it as a direct dependency of @plane/editor ensures it's
available in langium's resolve scope.
* ci: include lockfile hash in Turbo cache key to prevent stale hits
When pnpm-lock.yaml changes (e.g. new dependency added), the old Turbo
cache could still match via restore-keys fallback, causing CI to skip
rebuilding affected packages and miss build errors.
Adding hashFiles('pnpm-lock.yaml') to the cache key ensures dependency
changes invalidate the Turbo cache.
