Replace CORS proxy with complete server-side cache

- Replace cors/ directory and cors.mjs utility with comprehensive
    HTTP caching proxy in proxy/ directory
- Implement RFC-compliant caching with cache-control headers,
    conditional requests, and in-flight deduplication
- Centralized error handling with "safe" fetch utilities
- Add unified proxy handlers for weather.gov, SPC, radar, and mesonet APIs
- Include cache management endpoint and extensive diagnostic logging
- Migrate client-side URL rewriting from cors.mjs to url-rewrite.mjs

server/scripts/modules/utils/cache.mjs

@@ -0,0 +1,40 @@
+import { rewriteUrl } from './url-rewrite.mjs';
+
+// Clear cache utility for client-side use
+const clearCacheEntry = async (url, baseUrl = '') => {
+	try {
+		// Rewrite the URL to get the local proxy path
+		const rewrittenUrl = rewriteUrl(url);
+		const urlObj = typeof rewrittenUrl === 'string' ? new URL(rewrittenUrl, baseUrl || window.location.origin) : rewrittenUrl;
+		let cachePath = urlObj.pathname + urlObj.search;
+
+		// Strip the route designator (first path segment) to match actual cache keys
+		const firstSlashIndex = cachePath.indexOf('/', 1); // Find second slash
+		if (firstSlashIndex > 0) {
+			cachePath = cachePath.substring(firstSlashIndex);
+		}
+
+		// Call the cache clear endpoint
+		const fetchUrl = baseUrl ? `${baseUrl}/cache${cachePath}` : `/cache${cachePath}`;
+		const response = await fetch(fetchUrl, {
+			method: 'DELETE',
+		});
+
+		if (response.ok) {
+			const result = await response.json();
+			if (result.cleared) {
+				console.log(`🗑️ Cleared cache entry: ${cachePath}`);
+				return true;
+			}
+			console.log(`🔍 Cache entry not found: ${cachePath}`);
+			return false;
+		}
+		console.warn(`⚠️ Failed to clear cache entry: ${response.status} ${response.statusText}`);
+		return false;
+	} catch (error) {
+		console.error(`❌ Error clearing cache entry for ${url}:`, error.message);
+		return false;
+	}
+};
+
+export default clearCacheEntry;