refactor: reorganize docker role into logical service groups

Break down the monolithic main.yml (176 lines) into organized service categories:

- infrastructure/ (caddy, authentik, dockge) - Core platform components
- development/ (gitea, codeserver, conduit) - Development tools
- media/ (audiobookshelf, calibre, ghost, pinchflat, etc.) - Content services
- productivity/ (paperless, baikal, syncthing, mmdl, etc.) - Personal organization
- monitoring/ (glance, changedetection, appriseapi) - System monitoring
- communication/ (gotosocial, postiz) - Social/messaging services

Benefits:
- Improved maintainability with logical grouping
- Better dependency management between service categories
- Enhanced tag-based deployment (can deploy by category)
- Cleaner organization for 25+ services

All individual service tags remain functional for backwards compatibility.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

roles/docker/tasks/communication/main.yml

@@ -0,0 +1,10 @@
+---
+# Communication services - Social media, messaging, and external communication
+
+- name: Install gotosocial
+  import_tasks: gotosocial.yml
+  tags: gotosocial
+
+- name: Install postiz
+  import_tasks: postiz.yml
+  tags: postiz