feat(build): GitLab CI component, GitHub Actions action, and pre-commit hook

templates/check.yml — GitLab CI/CD Catalog component; downloads the glint
Linux binary and runs glint check; inputs: stage, pipeline_file, version,
allow_failure, extra_args.

action.yml — GitHub Actions composite action; downloads glint into
$RUNNER_TEMP and runs glint check; inputs: version, file, args. Mirror
to github.com/k3nny/glint to use as `uses: k3nny/glint@vX.Y.Z`.

.pre-commit-hooks.yaml — language: golang hook; pre-commit builds glint
from source on first run and re-runs on staged .gitlab-ci.yml changes.
Reference as repo: https://git.k3nny.fr/k3nny/glint.

README updated with an Integrations section covering all three.
Git remote corrected to https://git.k3nny.fr/k3nny/glint.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.pre-commit-hooks.yaml

@@ -0,0 +1,11 @@
+- id: glint
+  name: glint — validate GitLab CI pipeline
+  description: >-
+    Lint .gitlab-ci.yml with glint before committing. Catches misconfigured
+    stages, invalid keywords, broken needs: graphs, deprecated patterns, and
+    more — without a GitLab server.
+  entry: glint check
+  language: golang
+  files: '(^|/)\.gitlab-ci\.yml$'
+  pass_filenames: true
+  minimum_pre_commit_version: '3.0.0'