chore: update copyright year 2025 -> 2026 in lessons

Update copyright year in semantic-containers lesson example
across all language versions.

lessons/20-html-elements.json

@@ -34,12 +34,12 @@
 			"id": "semantic-containers",
 			"title": "Semantic Tags",
 			"description": "Modern HTML uses semantic containers that describe their content:<br><br><kbd>&lt;header&gt;</kbd> - Page or section header<br><kbd>&lt;nav&gt;</kbd> - Navigation links<br><kbd>&lt;main&gt;</kbd> - Main content area<br><kbd>&lt;section&gt;</kbd> - Thematic grouping<br><kbd>&lt;article&gt;</kbd> - Self-contained content<br><kbd>&lt;footer&gt;</kbd> - Page or section footer",
-			"task": "Create a basic page structure:<br>1. Add a <kbd>&lt;header&gt;</kbd> with an <kbd>&lt;h1&gt;</kbd> containing the text <code>My Website</code><br>2. Add a <kbd>&lt;main&gt;</kbd> element with a paragraph saying <code>Welcome to my site!</code><br>3. Add a <kbd>&lt;footer&gt;</kbd> with a paragraph saying <code>Copyright 2025</code>",
+			"task": "Create a basic page structure:<br>1. Add a <kbd>&lt;header&gt;</kbd> with an <kbd>&lt;h1&gt;</kbd> containing the text <code>My Website</code><br>2. Add a <kbd>&lt;main&gt;</kbd> element with a paragraph saying <code>Welcome to my site!</code><br>3. Add a <kbd>&lt;footer&gt;</kbd> with a paragraph saying <code>Copyright 2026</code>",
 			"previewHTML": "",
 			"previewBaseCSS": "body { font-family: system-ui; margin: 0; } header { background: #1976d2; color: white; padding: 15px; } main { padding: 20px; min-height: 100px; } footer { background: #424242; color: white; padding: 10px; text-align: center; }",
 			"sandboxCSS": "",
 			"initialCode": "",
-			"solution": "<header>\n  <h1>My Website</h1>\n</header>\n<main>\n  <p>Welcome to my site!</p>\n</main>\n<footer>\n  <p>Copyright 2025</p>\n</footer>",
+			"solution": "<header>\n  <h1>My Website</h1>\n</header>\n<main>\n  <p>Welcome to my site!</p>\n</main>\n<footer>\n  <p>Copyright 2026</p>\n</footer>",
 			"previewContainer": "preview-area",
 			"validations": [
 				{

lessons/ar/20-html-elements.json

@@ -34,12 +34,12 @@
 			"id": "semantic-containers",
 			"title": "Semantic Tags",
 			"description": "Modern HTML uses semantic containers that describe their content:<br><br><kbd>&lt;header&gt;</kbd> - Page or section header<br><kbd>&lt;nav&gt;</kbd> - Navigation links<br><kbd>&lt;main&gt;</kbd> - Main content area<br><kbd>&lt;section&gt;</kbd> - Thematic grouping<br><kbd>&lt;article&gt;</kbd> - Self-contained content<br><kbd>&lt;footer&gt;</kbd> - Page or section footer",
-			"task": "Create a basic page structure:<br>1. Add a <kbd>&lt;header&gt;</kbd> with an <kbd>&lt;h1&gt;</kbd> containing the text <code>My Website</code><br>2. Add a <kbd>&lt;main&gt;</kbd> element with a paragraph saying <code>Welcome to my site!</code><br>3. Add a <kbd>&lt;footer&gt;</kbd> with a paragraph saying <code>Copyright 2025</code>",
+			"task": "Create a basic page structure:<br>1. Add a <kbd>&lt;header&gt;</kbd> with an <kbd>&lt;h1&gt;</kbd> containing the text <code>My Website</code><br>2. Add a <kbd>&lt;main&gt;</kbd> element with a paragraph saying <code>Welcome to my site!</code><br>3. Add a <kbd>&lt;footer&gt;</kbd> with a paragraph saying <code>Copyright 2026</code>",
 			"previewHTML": "",
 			"previewBaseCSS": "body { font-family: system-ui; margin: 0; } header { background: #1976d2; color: white; padding: 15px; } main { padding: 20px; min-height: 100px; } footer { background: #424242; color: white; padding: 10px; text-align: center; }",
 			"sandboxCSS": "",
 			"initialCode": "",
-			"solution": "<header>\n  <h1>My Website</h1>\n</header>\n<main>\n  <p>Welcome to my site!</p>\n</main>\n<footer>\n  <p>Copyright 2025</p>\n</footer>",
+			"solution": "<header>\n  <h1>My Website</h1>\n</header>\n<main>\n  <p>Welcome to my site!</p>\n</main>\n<footer>\n  <p>Copyright 2026</p>\n</footer>",
 			"previewContainer": "preview-area",
 			"validations": [
 				{

lessons/de/20-html-elements.json

@@ -34,12 +34,12 @@
 			"id": "semantic-containers",
 			"title": "Semantische Container-Elemente",
 			"description": "Modernes HTML verwendet semantische Container, die ihren Inhalt beschreiben:<br><br><kbd>&lt;header&gt;</kbd> - Kopfbereich der Seite oder eines Abschnitts<br><kbd>&lt;nav&gt;</kbd> - Navigationslinks<br><kbd>&lt;main&gt;</kbd> - Hauptinhalt<br><kbd>&lt;section&gt;</kbd> - Thematische Gruppierung<br><kbd>&lt;article&gt;</kbd> - Eigenständiger Inhalt<br><kbd>&lt;footer&gt;</kbd> - Fußbereich der Seite oder eines Abschnitts",
-			"task": "Erstelle eine einfache Seitenstruktur:<br>1. Füge ein <kbd>&lt;header&gt;</kbd> mit einem <kbd>&lt;h1&gt;</kbd> hinzu, das den Text <code>Meine Webseite</code> enthält<br>2. Füge ein <kbd>&lt;main&gt;</kbd>-Element mit einem Absatz hinzu, der <code>Willkommen auf meiner Seite!</code> sagt<br>3. Füge ein <kbd>&lt;footer&gt;</kbd> mit einem Absatz hinzu, der <code>Copyright 2025</code> sagt",
+			"task": "Erstelle eine einfache Seitenstruktur:<br>1. Füge ein <kbd>&lt;header&gt;</kbd> mit einem <kbd>&lt;h1&gt;</kbd> hinzu, das den Text <code>Meine Webseite</code> enthält<br>2. Füge ein <kbd>&lt;main&gt;</kbd>-Element mit einem Absatz hinzu, der <code>Willkommen auf meiner Seite!</code> sagt<br>3. Füge ein <kbd>&lt;footer&gt;</kbd> mit einem Absatz hinzu, der <code>Copyright 2026</code> sagt",
 			"previewHTML": "",
 			"previewBaseCSS": "body { font-family: system-ui; margin: 0; } header { background: #1976d2; color: white; padding: 15px; } main { padding: 20px; min-height: 100px; } footer { background: #424242; color: white; padding: 10px; text-align: center; }",
 			"sandboxCSS": "",
 			"initialCode": "",
-			"solution": "<header>\n  <h1>Meine Webseite</h1>\n</header>\n<main>\n  <p>Willkommen auf meiner Seite!</p>\n</main>\n<footer>\n  <p>Copyright 2025</p>\n</footer>",
+			"solution": "<header>\n  <h1>Meine Webseite</h1>\n</header>\n<main>\n  <p>Willkommen auf meiner Seite!</p>\n</main>\n<footer>\n  <p>Copyright 2026</p>\n</footer>",
 			"previewContainer": "preview-area",
 			"validations": [
 				{

lessons/es/20-html-elements.json

@@ -34,12 +34,12 @@
 			"id": "semantic-containers",
 			"title": "Semantic Tags",
 			"description": "Modern HTML uses semantic containers that describe their content:<br><br><kbd>&lt;header&gt;</kbd> - Page or section header<br><kbd>&lt;nav&gt;</kbd> - Navigation links<br><kbd>&lt;main&gt;</kbd> - Main content area<br><kbd>&lt;section&gt;</kbd> - Thematic grouping<br><kbd>&lt;article&gt;</kbd> - Self-contained content<br><kbd>&lt;footer&gt;</kbd> - Page or section footer",
-			"task": "Create a basic page structure:<br>1. Add a <kbd>&lt;header&gt;</kbd> with an <kbd>&lt;h1&gt;</kbd> containing the text <code>My Website</code><br>2. Add a <kbd>&lt;main&gt;</kbd> element with a paragraph saying <code>Welcome to my site!</code><br>3. Add a <kbd>&lt;footer&gt;</kbd> with a paragraph saying <code>Copyright 2025</code>",
+			"task": "Create a basic page structure:<br>1. Add a <kbd>&lt;header&gt;</kbd> with an <kbd>&lt;h1&gt;</kbd> containing the text <code>My Website</code><br>2. Add a <kbd>&lt;main&gt;</kbd> element with a paragraph saying <code>Welcome to my site!</code><br>3. Add a <kbd>&lt;footer&gt;</kbd> with a paragraph saying <code>Copyright 2026</code>",
 			"previewHTML": "",
 			"previewBaseCSS": "body { font-family: system-ui; margin: 0; } header { background: #1976d2; color: white; padding: 15px; } main { padding: 20px; min-height: 100px; } footer { background: #424242; color: white; padding: 10px; text-align: center; }",
 			"sandboxCSS": "",
 			"initialCode": "",
-			"solution": "<header>\n  <h1>My Website</h1>\n</header>\n<main>\n  <p>Welcome to my site!</p>\n</main>\n<footer>\n  <p>Copyright 2025</p>\n</footer>",
+			"solution": "<header>\n  <h1>My Website</h1>\n</header>\n<main>\n  <p>Welcome to my site!</p>\n</main>\n<footer>\n  <p>Copyright 2026</p>\n</footer>",
 			"previewContainer": "preview-area",
 			"validations": [
 				{

lessons/pl/20-html-elements.json

@@ -34,12 +34,12 @@
 			"id": "semantic-containers",
 			"title": "Semantic Tags",
 			"description": "Modern HTML uses semantic containers that describe their content:<br><br><kbd>&lt;header&gt;</kbd> - Page or section header<br><kbd>&lt;nav&gt;</kbd> - Navigation links<br><kbd>&lt;main&gt;</kbd> - Main content area<br><kbd>&lt;section&gt;</kbd> - Thematic grouping<br><kbd>&lt;article&gt;</kbd> - Self-contained content<br><kbd>&lt;footer&gt;</kbd> - Page or section footer",
-			"task": "Create a basic page structure:<br>1. Add a <kbd>&lt;header&gt;</kbd> with an <kbd>&lt;h1&gt;</kbd> containing the text <code>My Website</code><br>2. Add a <kbd>&lt;main&gt;</kbd> element with a paragraph saying <code>Welcome to my site!</code><br>3. Add a <kbd>&lt;footer&gt;</kbd> with a paragraph saying <code>Copyright 2025</code>",
+			"task": "Create a basic page structure:<br>1. Add a <kbd>&lt;header&gt;</kbd> with an <kbd>&lt;h1&gt;</kbd> containing the text <code>My Website</code><br>2. Add a <kbd>&lt;main&gt;</kbd> element with a paragraph saying <code>Welcome to my site!</code><br>3. Add a <kbd>&lt;footer&gt;</kbd> with a paragraph saying <code>Copyright 2026</code>",
 			"previewHTML": "",
 			"previewBaseCSS": "body { font-family: system-ui; margin: 0; } header { background: #1976d2; color: white; padding: 15px; } main { padding: 20px; min-height: 100px; } footer { background: #424242; color: white; padding: 10px; text-align: center; }",
 			"sandboxCSS": "",
 			"initialCode": "",
-			"solution": "<header>\n  <h1>My Website</h1>\n</header>\n<main>\n  <p>Welcome to my site!</p>\n</main>\n<footer>\n  <p>Copyright 2025</p>\n</footer>",
+			"solution": "<header>\n  <h1>My Website</h1>\n</header>\n<main>\n  <p>Welcome to my site!</p>\n</main>\n<footer>\n  <p>Copyright 2026</p>\n</footer>",
 			"previewContainer": "preview-area",
 			"validations": [
 				{

lessons/uk/20-html-elements.json

@@ -34,12 +34,12 @@
 			"id": "semantic-containers",
 			"title": "Semantic Tags",
 			"description": "Modern HTML uses semantic containers that describe their content:<br><br><kbd>&lt;header&gt;</kbd> - Page or section header<br><kbd>&lt;nav&gt;</kbd> - Navigation links<br><kbd>&lt;main&gt;</kbd> - Main content area<br><kbd>&lt;section&gt;</kbd> - Thematic grouping<br><kbd>&lt;article&gt;</kbd> - Self-contained content<br><kbd>&lt;footer&gt;</kbd> - Page or section footer",
-			"task": "Create a basic page structure:<br>1. Add a <kbd>&lt;header&gt;</kbd> with an <kbd>&lt;h1&gt;</kbd> containing the text <code>My Website</code><br>2. Add a <kbd>&lt;main&gt;</kbd> element with a paragraph saying <code>Welcome to my site!</code><br>3. Add a <kbd>&lt;footer&gt;</kbd> with a paragraph saying <code>Copyright 2025</code>",
+			"task": "Create a basic page structure:<br>1. Add a <kbd>&lt;header&gt;</kbd> with an <kbd>&lt;h1&gt;</kbd> containing the text <code>My Website</code><br>2. Add a <kbd>&lt;main&gt;</kbd> element with a paragraph saying <code>Welcome to my site!</code><br>3. Add a <kbd>&lt;footer&gt;</kbd> with a paragraph saying <code>Copyright 2026</code>",
 			"previewHTML": "",
 			"previewBaseCSS": "body { font-family: system-ui; margin: 0; } header { background: #1976d2; color: white; padding: 15px; } main { padding: 20px; min-height: 100px; } footer { background: #424242; color: white; padding: 10px; text-align: center; }",
 			"sandboxCSS": "",
 			"initialCode": "",
-			"solution": "<header>\n  <h1>My Website</h1>\n</header>\n<main>\n  <p>Welcome to my site!</p>\n</main>\n<footer>\n  <p>Copyright 2025</p>\n</footer>",
+			"solution": "<header>\n  <h1>My Website</h1>\n</header>\n<main>\n  <p>Welcome to my site!</p>\n</main>\n<footer>\n  <p>Copyright 2026</p>\n</footer>",
 			"previewContainer": "preview-area",
 			"validations": [
 				{