fix: resolve CI linting issues across codebase

- Remove unused imports (sys, Path, defaultdict, etc.)
- Convert Optional types to modern | syntax
- Fix trailing whitespace and blank line whitespace issues
- Sort imports alphabetically
- Add __future__ annotations for type syntax support

src/codesnap/core/analyzer.py

@@ -0,0 +1,59 @@
+from __future__ import annotations
+
+import ast
+from pathlib import Path
+from codesnap.core.complexity import ComplexityCalculator
+from codesnap.core.dependency_graph import DependencyGraph
+from codesnap.core.models import FileSummary, FunctionInfo
+
+
+class CodeAnalyzer:
+    def __init__(self):
+        self.complexity_calc = ComplexityCalculator()
+        self.dep_graph = DependencyGraph()
+
+    def analyze_file(self, file_path: Path) -> FileSummary:
+        with open(file_path, "r", encoding="utf-8") as f:
+            content = f.read()
+
+        tree = ast.parse(content)
+
+        functions = []
+        for node in ast.walk(tree):
+            if isinstance(node, (ast.FunctionDef, ast.AsyncFunctionDef)):
+                func_info = self.complexity_calc.calculate_function_complexity(node, content)
+                functions.append(func_info)
+
+        self.dep_graph.add_file(file_path, tree)
+
+        imports = self._extract_imports(tree)
+
+        return FileSummary(
+            file_path=str(file_path),
+            functions=functions,
+            total_complexity=sum(f.complexity for f in functions),
+            imports=imports,
+        )
+
+    def analyze_directory(self, dir_path: Path) -> list[FileSummary]:
+        results = []
+        for py_file in dir_path.rglob("*.py"):
+            try:
+                summary = self.analyze_file(py_file)
+                results.append(summary)
+            except Exception as e:
+                print(f"Error analyzing {py_file}: {e}")
+
+        return results
+
+    def _extract_imports(self, tree: ast.AST) -> list[str]:
+        imports = []
+        for node in ast.walk(tree):
+            if isinstance(node, ast.Import):
+                for alias in node.names:
+                    imports.append(f"import {alias.name}")
+            elif isinstance(node, ast.ImportFrom):
+                module = node.module or ""
+                for alias in node.names:
+                    imports.append(f"from {module} import {alias.name}")
+        return imports