chore: migrate project to Bun testing framework and update configuration

- Replace Jest with Bun's native testing framework
- Update test configuration and utilities to support Bun test environment
- Add mock implementations for SSE and security testing
- Refactor test setup to use Bun's testing utilities
- Update package dependencies and scripts to align with Bun testing
- Enhance type definitions for Bun test mocking

src/types/bun.d.ts

@@ -0,0 +1,50 @@
+declare module 'bun:test' {
+    export interface Mock<T extends (...args: any[]) => any> {
+        (...args: Parameters<T>): ReturnType<T>;
+        mock: {
+            calls: Array<{ args: Parameters<T>; returned: ReturnType<T> }>;
+            results: Array<{ type: 'return' | 'throw'; value: any }>;
+            instances: any[];
+            lastCall: { args: Parameters<T>; returned: ReturnType<T> } | undefined;
+        };
+        mockImplementation(fn: T): this;
+        mockReturnValue(value: ReturnType<T>): this;
+        mockResolvedValue<U>(value: U): Mock<() => Promise<U>>;
+        mockRejectedValue(value: any): Mock<() => Promise<never>>;
+        mockReset(): void;
+    }
+
+    export function mock<T extends (...args: any[]) => any>(
+        implementation?: T
+    ): Mock<T>;
+
+    export function describe(name: string, fn: () => void): void;
+    export function it(name: string, fn: () => void | Promise<void>): void;
+    export function test(name: string, fn: () => void | Promise<void>): void;
+    export function expect(actual: any): {
+        toBe(expected: any): void;
+        toEqual(expected: any): void;
+        toBeDefined(): void;
+        toBeUndefined(): void;
+        toBeNull(): void;
+        toBeTruthy(): void;
+        toBeFalsy(): void;
+        toBeGreaterThan(expected: number): void;
+        toBeLessThan(expected: number): void;
+        toContain(expected: any): void;
+        toHaveLength(expected: number): void;
+        toHaveBeenCalled(): void;
+        toHaveBeenCalledTimes(expected: number): void;
+        toHaveBeenCalledWith(...args: any[]): void;
+        toThrow(expected?: string | RegExp): void;
+        resolves: any;
+        rejects: any;
+    };
+    export function beforeAll(fn: () => void | Promise<void>): void;
+    export function afterAll(fn: () => void | Promise<void>): void;
+    export function beforeEach(fn: () => void | Promise<void>): void;
+    export function afterEach(fn: () => void | Promise<void>): void;
+    export const mock: {
+        resetAll(): void;
+    };
+}