Separate community stats workflow (#85)

## Summary
- remove the GitHub Pages deployment workflow
- retain community-stat updates in a standalone scheduled workflow
- grant the stats workflow permission to commit refreshed data

## Verification
- reviewed the revised workflow inventory and standalone workflow
configuration
- local Actions linting was unavailable because `actionlint` is not
installed

Author: HeyItsGilbert

.github/workflows/discourse-sync.yml .github/workflows/community-stats.yml.github/workflows/discourse-sync.yml renamed to .github/workflows/community-stats.yml

@@ -5,6 +5,9 @@ on:
     - cron: '0 */4 * * *'  # Every 4 hours
   workflow_dispatch:
 
+permissions:
+  contents: write
+
 jobs:
   update-community:
     runs-on: ubuntu-latest