feat: merge chess_tutor + OpenRouter abstraction

- Merged stefan-kp/chess_tutor into chess-project with full feature set
- Preserved Hermes agent files (agents/, .gitea/, AGENTS.md)
- Added OpenRouter abstraction layer (src/lib/openrouter.ts)
- Created ModelSelector dropdown component with 9 models
- Updated API routes (chat + opening explanation) to use OpenRouter
- Updated useTutorChat to route through OpenRouter API
- Updated onboarding and API key input for OpenRouter
- Created tasks.md with sprint 1 plan
- Updated README with new architecture details

.gitea/ISSUE_TEMPLATE/feature.md

@@ -0,0 +1,22 @@
+---
+name: Feature Request
+about: Suggest a new feature for this project
+title: '[FEATURE] '
+labels: feature
+---
+
+## Description
+
+## Motivation
+
+## Proposed Solution
+
+## Acceptance Criteria
+
+- [ ] 
+- [ ] 
+- [ ] 
+
+## Related Planning
+
+Reference any related issues or plans from the `core-planning` repository.