refactor: create registry, cfg, and resolution packages

This PR establishes the infrastructure core by creating three new packages
that resolve circular dependencies and improve code organization. The
registry package handles module/type/attribute registries, cfg package
manages control flow graphs, and resolution package defines type resolution
structures. All changes maintain backward compatibility through type aliases.

Verification: gradle buildGo (success), gradle testGo (all pass), gradle
lintGo (0 issues), coverage 95.9-100% across new packages.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: shivasurya

.vscode/settings.json

@@ -0,0 +1,3 @@
+{
+    "python.languageServer": "None"
+}

sourcecode-parser/graph/callgraph/attribute_extraction.go

@@ -7,6 +7,7 @@ import (
 	sitter "github.com/smacker/go-tree-sitter"
 	"github.com/smacker/go-tree-sitter/python"
 	"github.com/shivasurya/code-pathfinder/sourcecode-parser/graph"
+	"github.com/shivasurya/code-pathfinder/sourcecode-parser/graph/callgraph/registry"
 )
 
 // ExtractClassAttributes extracts all class attributes from a Python file
@@ -37,7 +38,7 @@ func ExtractClassAttributes(
 	sourceCode []byte,
 	modulePath string,
 	typeEngine *TypeInferenceEngine,
-	registry *AttributeRegistry,
+	attrRegistry *registry.AttributeRegistry,
 ) error {
 	// Parse file with tree-sitter
 	parser := sitter.NewParser()
@@ -94,7 +95,7 @@ func ExtractClassAttributes(
 		classAttrs.Attributes = attributeMap
 
 		// Add to registry
-		registry.AddClassAttributes(classAttrs)
+		attrRegistry.AddClassAttributes(classAttrs)
 	}
 
 	return nil

sourcecode-parser/graph/callgraph/attribute_registry.go

@@ -1,9 +1,8 @@
 package callgraph
 
 import (
-	"sync"
-
 	"github.com/shivasurya/code-pathfinder/sourcecode-parser/graph/callgraph/core"
+	"github.com/shivasurya/code-pathfinder/sourcecode-parser/graph/callgraph/registry"
 )
 
 // Deprecated: Use core.ClassAttribute instead.
@@ -14,92 +13,12 @@ type ClassAttribute = core.ClassAttribute
 // This alias will be removed in a future version.
 type ClassAttributes = core.ClassAttributes
 
-// AttributeRegistry is the global registry of class attributes
-// It provides thread-safe access to class attribute information.
-type AttributeRegistry struct {
-	Classes map[string]*ClassAttributes // Map from class FQN to class attributes
-	mu      sync.RWMutex                // Protects concurrent access
-}
+// Deprecated: Use registry.AttributeRegistry instead.
+// This alias will be removed in a future version.
+type AttributeRegistry = registry.AttributeRegistry
 
 // NewAttributeRegistry creates a new empty AttributeRegistry.
+// Deprecated: Use registry.NewAttributeRegistry instead.
 func NewAttributeRegistry() *AttributeRegistry {
-	return &AttributeRegistry{
-		Classes: make(map[string]*ClassAttributes),
-	}
-}
-
-// GetClassAttributes retrieves attributes for a given class FQN
-// Returns nil if class is not in registry.
-func (ar *AttributeRegistry) GetClassAttributes(classFQN string) *ClassAttributes {
-	ar.mu.RLock()
-	defer ar.mu.RUnlock()
-	return ar.Classes[classFQN]
-}
-
-// GetAttribute retrieves a specific attribute from a class
-// Returns nil if class or attribute is not found.
-func (ar *AttributeRegistry) GetAttribute(classFQN, attrName string) *ClassAttribute {
-	ar.mu.RLock()
-	defer ar.mu.RUnlock()
-
-	classAttrs, exists := ar.Classes[classFQN]
-	if !exists || classAttrs == nil {
-		return nil
-	}
-
-	return classAttrs.Attributes[attrName]
-}
-
-// AddClassAttributes adds or updates attributes for a class
-// Thread-safe for concurrent modifications.
-func (ar *AttributeRegistry) AddClassAttributes(classAttrs *ClassAttributes) {
-	ar.mu.Lock()
-	defer ar.mu.Unlock()
-	ar.Classes[classAttrs.ClassFQN] = classAttrs
-}
-
-// AddAttribute adds a single attribute to a class
-// Creates the ClassAttributes entry if it doesn't exist.
-func (ar *AttributeRegistry) AddAttribute(classFQN string, attr *ClassAttribute) {
-	ar.mu.Lock()
-	defer ar.mu.Unlock()
-
-	classAttrs, exists := ar.Classes[classFQN]
-	if !exists {
-		classAttrs = &ClassAttributes{
-			ClassFQN:   classFQN,
-			Attributes: make(map[string]*ClassAttribute),
-			Methods:    []string{},
-		}
-		ar.Classes[classFQN] = classAttrs
-	}
-
-	classAttrs.Attributes[attr.Name] = attr
-}
-
-// HasClass checks if a class is registered.
-func (ar *AttributeRegistry) HasClass(classFQN string) bool {
-	ar.mu.RLock()
-	defer ar.mu.RUnlock()
-	_, exists := ar.Classes[classFQN]
-	return exists
-}
-
-// GetAllClasses returns a list of all registered class FQNs.
-func (ar *AttributeRegistry) GetAllClasses() []string {
-	ar.mu.RLock()
-	defer ar.mu.RUnlock()
-
-	classes := make([]string, 0, len(ar.Classes))
-	for classFQN := range ar.Classes {
-		classes = append(classes, classFQN)
-	}
-	return classes
-}
-
-// Size returns the number of registered classes.
-func (ar *AttributeRegistry) Size() int {
-	ar.mu.RLock()
-	defer ar.mu.RUnlock()
-	return len(ar.Classes)
+	return registry.NewAttributeRegistry()
 }

sourcecode-parser/graph/callgraph/attribute_resolution.go

@@ -5,6 +5,7 @@ import (
 	"strings"
 
 	"github.com/shivasurya/code-pathfinder/sourcecode-parser/graph"
+	"github.com/shivasurya/code-pathfinder/sourcecode-parser/graph/callgraph/registry"
 )
 
 // FailureStats tracks why attribute chain resolution fails.
@@ -63,7 +64,7 @@ func ResolveSelfAttributeCall(
 	target string,
 	callerFQN string,
 	typeEngine *TypeInferenceEngine,
-	builtins *BuiltinRegistry,
+	builtins *registry.BuiltinRegistry,
 	callGraph *CallGraph,
 ) (string, bool, *TypeInfo) {
 	attributeFailureStats.TotalAttempts++
@@ -228,7 +229,7 @@ func PrintAttributeFailureStats() {
 //
 // Returns:
 //   - class FQN if found, empty string otherwise
-func findClassContainingMethod(methodFQN string, registry *AttributeRegistry) string {
+func findClassContainingMethod(methodFQN string, registry *registry.AttributeRegistry) string {
 	// Extract method name from FQN (last part after final dot)
 	methodName := methodFQN
 	if lastDot := strings.LastIndex(methodFQN, "."); lastDot != -1 {
@@ -269,7 +270,7 @@ func findClassContainingMethod(methodFQN string, registry *AttributeRegistry) st
 //   - moduleRegistry: module registry for resolving class names
 //   - codeGraph: code graph for finding class definitions
 func ResolveAttributePlaceholders(
-	registry *AttributeRegistry,
+	registry *registry.AttributeRegistry,
 	typeEngine *TypeInferenceEngine,
 	moduleRegistry *ModuleRegistry,
 	codeGraph *graph.CodeGraph,

sourcecode-parser/graph/callgraph/builder.go

@@ -9,6 +9,7 @@ import (
 
 	sitter "github.com/smacker/go-tree-sitter"
 	"github.com/shivasurya/code-pathfinder/sourcecode-parser/graph"
+	cgregistry "github.com/shivasurya/code-pathfinder/sourcecode-parser/graph/callgraph/registry"
 )
 
 // ImportMapCache provides thread-safe caching of ImportMap instances.
@@ -142,10 +143,10 @@ func BuildCallGraph(codeGraph *graph.CodeGraph, registry *ModuleRegistry, projec
 
 	// Initialize type inference engine
 	typeEngine := NewTypeInferenceEngine(registry)
-	typeEngine.Builtins = NewBuiltinRegistry()
+	typeEngine.Builtins = cgregistry.NewBuiltinRegistry()
 
 	// Phase 3 Task 12: Initialize attribute registry for tracking class attributes
-	typeEngine.Attributes = NewAttributeRegistry()
+	typeEngine.Attributes = cgregistry.NewAttributeRegistry()
 
 	// PR #3: Detect Python version and load stdlib registry from remote CDN
 	pythonVersion := detectPythonVersion(projectRoot)