feat(service): expand service layer with new domain operations

- Add IM service modules: audit, channel roles, custom emojis, forum
  tags, integrations, invitations, repo links, slash commands, stages,
  voice, webhooks
- Add PR service modules: review requests, templates
- Add repo service modules: contributors, release assets, git extras
  (archive, branch rename, commit extras, diff/merge, tag, tree)
- Add user service: social (follow/block)
- Add internal auth service
- Update existing service modules with expanded functionality
- Remove deleted IM modules: articles, delivery trace, drafts,
  follows, messages, polls, presence, reactions, threads

service/pr/mod.rs

@@ -7,7 +7,9 @@ pub mod files;
 pub mod labels;
 pub mod merge_strategy;
 pub mod reactions;
+pub mod review_requests;
 pub mod reviews;
 pub mod status;
 pub mod subscriptions;
+pub mod templates;
 pub mod util;