chore: release v2.0.0

- Remove Roadmap section from README (no longer representative)
- Update all version references to 2.0.0
- marketplace.json: 2.0.0
- projman plugin: 2.0.0
- Update documentation version references

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

plugins/projman/.claude-plugin/plugin.json

@@ -1,6 +1,6 @@
 {
   "name": "projman",
-  "version": "1.0.0",
+  "version": "2.0.0",
   "description": "Sprint planning and project management with Gitea integration",
   "author": {
     "name": "Bandit Labs",