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/ratelimit/RateLimiter.java

@@ -0,0 +1,21 @@
+package dev.coph.nextusweb.server.ratelimit;
+
+public interface RateLimiter {
+
+    Result tryAcquire(String key, long nowNanos);
+
+    record Result(
+            boolean allowed,
+            long remaining,
+            long limit,
+            long retryAfterMillis
+    ) {
+        public static Result allow(long remaining, long limit) {
+            return new Result(true, remaining, limit, 0);
+        }
+
+        public static Result deny(long limit, long retryAfterMillis) {
+            return new Result(false, 0, limit, retryAfterMillis);
+        }
+    }
+}