fix: ConfigTemplate infinite re-render loop and add E2E test

e2e/environment.spec.ts

@@ -105,4 +105,55 @@ test.describe('Environment Management', () => {
     await page.waitForTimeout(200);
     await expect(page.locator('#environments')).toBeVisible();
   });
+
+  test('should add params and edit template manually', async ({ page }) => {
+    await page.goto('/');
+    await page.click('button:has-text("Create new")');
+
+    // Step 1: Add a param to DEFAULT
+    const nameInput = page.locator('input[placeholder="name"]').first();
+    const valueInput = page.locator('input[placeholder="value"]').first();
+    const addButton = page.locator('button.btn-success').first();
+    
+    await nameInput.fill('host');
+    await valueInput.fill('localhost:8080');
+    await addButton.click();
+    await page.waitForTimeout(500);
+
+    // Add second param
+    await nameInput.fill('port');
+    await valueInput.fill('9090');
+    await addButton.click();
+    await page.waitForTimeout(500);
+
+    // Step 2: Switch to Content Template tab
+    await page.click('a:has-text("Content Template")');
+    await page.waitForTimeout(500);
+
+    // Verify the tab content is visible (check for Edit button)
+    await expect(page.locator('button:has-text("Edit")')).toBeVisible();
+
+    // Step 3: Click Edit button
+    await page.click('button:has-text("Edit")');
+    await page.waitForTimeout(500);
+
+    // Step 4: Verify textarea is visible
+    const textarea = page.locator('textarea');
+    await expect(textarea).toBeVisible();
+    
+    // Step 5: Edit the template manually - add a new key
+    await textarea.fill('{\n    "!!! host": "@host@",\n    "!!! port": "@port@",\n    "!!! custom": "@custom@"\n}');
+    await page.waitForTimeout(300);
+
+    // Step 6: Click Save
+    await page.click('button:has-text("Save")');
+    await page.waitForTimeout(500);
+
+    // Step 7: Verify the template was saved (Edit button should be visible again)
+    await expect(page.locator('button:has-text("Edit")')).toBeVisible();
+    
+    // Verify the content contains the new key
+    const pageContent = await page.content();
+    expect(pageContent).toContain('!!! custom');
+  });
 });

src/componets/content/ConfigTemplate.tsx

@@ -1,4 +1,4 @@
-import { useState } from "react";
+import { useState, useEffect } from "react";
 import Highlight from 'react-highlight';
 import 'highlight.js/styles/far.css';
 import { Config } from "../../models/Config";
@@ -14,10 +14,12 @@ export function ConfigTemplate(props: ConfigTemplateProps) {
   const [originalContent, setOriginalContent] = useState(props.config.template.content);
   const [jsonError, setJsonError] = useState<string | null>(null);
 
-  // Sync draft when config changes (in view mode)
+  // Sync draft when config changes (only in view mode)
+  useEffect(() => {
     if (mode === 'view') {
       setDraftContent(props.config.template.content);
     }
+  }, [props.config.template.content, mode]);
 
   function handleEdit() {
     setOriginalContent(props.config.template.content);

src/componets/content/Content.tsx

@@ -12,7 +12,7 @@ export function Content(props: { config: Config, env: Env, onTemplateSaved: (new
 
     return (
         <>
-            <ContentTabs onSelected={(id) => setTab(id)} />
+            <ContentTabs onSelected={(id) => setTab(id)} selectedTab={selectTab} />
             <div className="">
                 {selectTab == ContentType.Env ? (<ContentParams env={props.env} />) : ""}
                 {selectTab == ContentType.Json ? (<ConfigTemplate config={props.config} onSaved={props.onTemplateSaved} />) : ""}
@@ -30,16 +30,13 @@ enum ContentType {
     Test = 3
 }
 
-function ContentTabs(props: { onSelected: (id: ContentType) => void }) {
-    const [selectTab, setSelect] = useState(ContentType.Env);
-
+function ContentTabs(props: { onSelected: (id: ContentType) => void, selectedTab: ContentType }) {
     function clickHandler(type: ContentType) {
-        setSelect(type);
         props.onSelected(type);
     }
 
     function isActive(type: ContentType): string {
-        return type == selectTab ? " active" : " ";
+        return type == props.selectedTab ? " active" : " ";
     }
 
     return (