feat(chunking): add AST-aware code chunking for Go, Python, TypeScript

- [x] Add language-specific chunkers with AST parsing (Go, Python, TypeScript)
- [x] Implement chunking manager to dispatch files to appropriate chunkers
- [x] Integrate code chunks into vector sync for semantic search
- [x] Add tree-sitter dependency for Python/TypeScript parsing
- [x] Reorder struct fields for consistency across codebase
- [x] Rename error variables to follow Go conventions (err → unmarshalErr, etc.)
- [x] Add code chunk metadata to vector documents (language, symbol name, line ranges)
- [x] Update worker service to initialize chunking pipeline with all three languages

pkg/similarity/clustering_test.go

@@ -12,9 +12,9 @@ import (
 
 func TestJaccardSimilarity(t *testing.T) {
 	tests := []struct {
-		name     string
 		set1     map[string]bool
 		set2     map[string]bool
+		name     string
 		expected float64
 	}{
 		{