Add rate limiting, CORS support, custom HTTP method annotations, and HTTP server enhancements

- Introduced rate limiting functionality with multiple algorithms (Token Bucket, Fixed Window, Leaky Bucket, Sliding Window) via `RateLimiter` interface.
- Added CORS handling with `CorsConfig` and `CorsHandler` for flexible origin, headers, and method configuration.
- Implemented support for custom HTTP methods via `PATCH` and `CUSTOM` annotations in `AnnotationScanner`.
- Enhanced `HttpServer` to support builder pattern and optional integrations for CORS and rate limiting.
- Updated `HttpRequestHandler` to incorporate CORS and rate limiting logic.

src/main/java/dev/coph/nextusweb/server/annotation/CUSTOM.java

@@ -0,0 +1,13 @@
+package dev.coph.nextusweb.server.annotation;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.METHOD)
+public @interface CUSTOM {
+    String method();
+    String value();
+}