refactor rewriters to modify html in single pass with multiple rewriters; improve html rewriter edge case handling

proxychain/responsemodifers/rewriters/after_dom_idle_script_injector.js

@@ -0,0 +1,27 @@
+(() => {
+    document.addEventListener('DOMContentLoaded', (event) => {
+        initIdleMutationObserver();
+    });
+    
+    function initIdleMutationObserver() {
+        let debounceTimer;
+        const debounceDelay = 500; // adjust the delay as needed
+    
+        const observer = new MutationObserver((mutations) => {
+            // Clear the previous timer and set a new one
+            clearTimeout(debounceTimer);
+            debounceTimer = setTimeout(() => {
+                execute();
+                observer.disconnect(); // Disconnect after first execution
+            }, debounceDelay);
+        });
+    
+        const config = { attributes: false, childList: true, subtree: true };
+        observer.observe(document.body, config);
+    }
+    
+    function execute() {
+        'SCRIPT_CONTENT_PARAM'
+        //console.log('DOM is now idle. Executing...');
+    }
+})();