feat: initial v0.1.0 MVP

Replaces Smush Pro's optimisation pipeline without the grey-wash bug.

CLI commands working:
  wp h4b-img status
  wp h4b-img optimise --id=<n>
  wp h4b-img bulk
  wp h4b-img rescue

Verified on dev.rds.ink:
- ICC profile preservation works (the Smush-bug fix)
- Bulk: 20 attachments → 487 KB saved (10.4%), 0 errors
- Rescue: end-to-end mechanism verified on WorkingAsOne_horse fixture
- WebP synchronous, AVIF queued via WP-Cron
- Originals backed up to wp-content/h4b-img-originals/

See CHANGELOG.md for details + ../DESIGN-h4b-image-optim.md for architecture.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,33 @@
+# macOS / editor noise
+.DS_Store
+Thumbs.db
+*.swp
+*~
+.idea/
+.vscode/
+
+# PHP build / dependencies (we vendor manually if needed)
+vendor/
+composer.lock
+.phpunit.result.cache
+
+# Generated assets we don't want committed
+*.tmp
+*.bak
+*.rescue.tmp
+*.h4b.tmp
+*.pngq.tmp
+
+# Test fixtures / outputs
+tests/output/
+tests/.coverage/
+coverage.xml
+phpunit.xml
+
+# Logs / state
+*.log
+debug.log
+
+# IDE / OS files
+.directory
+.project