feat: Enhance embedding management and model configuration

- Updated embedding_manager.py to include backend parameter in model configuration.
- Modified model_manager.py to utilize cache_name for ONNX models.
- Refactored hybrid_search.py to improve embedder initialization based on backend type.
- Added backend column to vector_store.py for better model configuration management.
- Implemented migration for existing database to include backend information.
- Enhanced API settings implementation with comprehensive provider and endpoint management.
- Introduced LiteLLM integration guide detailing configuration and usage.
- Added examples for LiteLLM usage in TypeScript.

.gemini/GEMINI.md

@@ -1,25 +1,62 @@
-# Gemini Code Guidelines
+
+## Code Quality Standards
+
+### Code Quality
+- Follow project's existing patterns
+- Match import style and naming conventions
+- Single responsibility per function/class
+- DRY (Don't Repeat Yourself)
+- YAGNI (You Aren't Gonna Need It)
+
+### Testing
+- Test all public functions
+- Test edge cases and error conditions
+- Mock external dependencies
+- Target 80%+ coverage
+
+### Error Handling
+- Proper try-catch blocks
+- Clear error messages
+- Graceful degradation
+- Don't expose sensitive info
 
 ## Core Principles
 
-**Thoroughness**:
-- Analyze ALL CONTEXT files completely
-- Check cross-file patterns and dependencies
-- Identify edge cases and quantify metrics
+**Incremental Progress**:
+- Small, testable changes
+- Commit working code frequently
+- Build on previous work (subtasks)
 
 **Evidence-Based**:
-- Quote relevant code with `file:line` references
-- Link related patterns across files
-- Support all claims with concrete examples
+- Study 3+ similar patterns before implementing
+- Match project style exactly
+- Verify with existing code
 
-**Actionable**:
-- Clear, specific recommendations (not vague)
-- Prioritized by impact
-- Incremental changes over big rewrites
+**Pragmatic**:
+- Boring solutions over clever code
+- Simple over complex
+- Adapt to project reality
 
-**Philosophy**:
-- **Simple over complex** - Avoid over-engineering
-- **Clear over clever** - Prefer obvious solutions
-- **Learn from existing** - Reference project patterns
-- **Pragmatic over dogmatic** - Adapt to project reality
-- **Incremental progress** - Small, testable changes
+**Context Continuity** (Multi-Task):
+- Leverage resume for consistency
+- Maintain established patterns
+- Test integration between subtasks
+
+## Execution Checklist
+
+**Before**:
+- [ ] Understand PURPOSE and TASK clearly
+- [ ] Review CONTEXT files, find 3+ patterns
+- [ ] Check RULES templates and constraints
+
+**During**:
+- [ ] Follow existing patterns exactly
+- [ ] Write tests alongside code
+- [ ] Run tests after every change
+- [ ] Commit working code incrementally
+
+**After**:
+- [ ] All tests pass
+- [ ] Coverage meets target
+- [ ] Build succeeds
+- [ ] All EXPECTED deliverables met