test: simplify test suite and remove redundant mocking infrastructure

- Remove complex mock implementations and type definitions
- Streamline test files to use direct tool imports
- Reduce test complexity by removing unnecessary mock setup
- Update test cases to work with simplified tool registration
- Remove deprecated test utility functions and interfaces

tsconfig.test.json

@@ -0,0 +1,23 @@
+{
+    "extends": "./tsconfig.json",
+    "compilerOptions": {
+        // Inherit base configuration, but override with more relaxed settings for tests
+        "strict": false,
+        "strictNullChecks": false,
+        "strictFunctionTypes": false,
+        "strictPropertyInitialization": false,
+        "noImplicitAny": false,
+        "noImplicitThis": false,
+        // Additional relaxations for test files
+        "allowUnreachableCode": true,
+        "allowUnusedLabels": true,
+        // Specific test-related compiler options
+        "types": [
+            "bun-types",
+            "@types/jest"
+        ]
+    },
+    "include": [
+        "__tests__/**/*"
+    ]
+}