feat(workflows): migrate legacy workflows and enhance example handling

- Migrated legacy workflow files from `packages/server/workflows/` to `packages/server/data/workflows/` when the new store is empty.
- Introduced new API endpoints to list and retrieve example workflows.
- Added a dialog component for selecting example workflows when creating new workflows.
- Updated workflow paths and configurations to reflect the new structure.
- Enhanced the README and AGENTS.md documentation to clarify workflow management and usage.

Co-authored-by: Nasyarobby Putra <nasyarobby@gmail.com>

.gitignore

@@ -10,11 +10,11 @@ packages/web/dist
 # Personal/local scripts and workflows (not for the repo)
 debug-*.js
 
-# Site-specific workflows (keep examples in workflows/default/)
-packages/server/workflows/local/
+# Legacy live workflow tree (migrated to packages/server/data/workflows/)
+packages/server/workflows/
 
 # Plugin install staging and per-plugin deps
 plugins/.staging-*
 plugins/*/node_modules/
 
-.gitea/workflows/
+.gitea/workflows/