Use `event.key` in examples instead of deprecated event.which

site/content/examples/06-lifecycle/02-update/App.svelte

@@ -20,7 +20,7 @@
 	];
 
 	function handleKeydown(event) {
-		if (event.which === 13) {
+		if (event.key === 'Enter') {
 			const text = event.target.value;
 			if (!text) return;
 

site/content/examples/06-lifecycle/03-tick/App.svelte

@@ -4,7 +4,7 @@
 	let text = `Select some text and hit the tab key to toggle uppercase`;
 
 	async function handleKeydown(event) {
-		if (event.which !== 9) return;
+		if (event.key !== 'Tab') return;
 
 		event.preventDefault();
 

site/content/examples/10-animations/00-animate/App.svelte

@@ -112,7 +112,7 @@
 	<input
 		class="new-todo"
 		placeholder="what needs to be done?"
-		on:keydown="{event => event.which === 13 && add(event.target)}"
+		on:keydown="{event => event.key === 'Enter' && add(event.target)}"
 	>
 
 	<div class='left'>

site/content/tutorial/07-lifecycle/03-update/app-a/App.svelte

@@ -20,7 +20,7 @@
 	];
 
 	function handleKeydown(event) {
-		if (event.which === 13) {
+		if (event.key === 'Enter') {
 			const text = event.target.value;
 			if (!text) return;
 

site/content/tutorial/07-lifecycle/03-update/app-b/App.svelte

@@ -20,7 +20,7 @@
 	];
 
 	function handleKeydown(event) {
-		if (event.which === 13) {
+		if (event.key === 'Enter') {
 			const text = event.target.value;
 			if (!text) return;
 

site/content/tutorial/07-lifecycle/04-tick/app-a/App.svelte

@@ -2,7 +2,7 @@
 	let text = `Select some text and hit the tab key to toggle uppercase`;
 
 	async function handleKeydown(event) {
-		if (event.which !== 9) return;
+		if (event.key !== 'Tab') return;
 
 		event.preventDefault();
 

site/content/tutorial/07-lifecycle/04-tick/app-b/App.svelte

@@ -4,7 +4,7 @@
 	let text = `Select some text and hit the tab key to toggle uppercase`;
 
 	async function handleKeydown(event) {
-		if (event.which !== 9) return;
+		if (event.key !== 'Tab') return;
 
 		event.preventDefault();
 

site/content/tutorial/10-transitions/08-deferred-transitions/app-a/App.svelte

@@ -56,7 +56,7 @@
 <div class='board'>
 	<input
 		placeholder="what needs to be done?"
-		on:keydown={e => e.which === 13 && add(e.target)}
+		on:keydown={e => e.key === 'Enter' && add(e.target)}
 	>
 
 	<div class='left'>

site/content/tutorial/10-transitions/08-deferred-transitions/app-b/App.svelte

@@ -56,7 +56,7 @@
 <div class='board'>
 	<input
 		placeholder="what needs to be done?"
-		on:keydown={e => e.which === 13 && add(e.target)}
+		on:keydown={e => e.key === 'Enter' && add(e.target)}
 	>
 
 	<div class='left'>

site/content/tutorial/11-animations/01-animate/app-a/App.svelte

@@ -56,7 +56,7 @@
 <div class='board'>
 	<input
 		placeholder="what needs to be done?"
-		on:keydown={e => e.which === 13 && add(e.target)}
+		on:keydown={e => e.key === 'Enter' && add(e.target)}
 	>
 
 	<div class='left'>

site/content/tutorial/11-animations/01-animate/app-b/App.svelte

@@ -57,7 +57,7 @@
 <div class='board'>
 	<input
 		placeholder="what needs to be done?"
-		on:keydown={e => e.which === 13 && add(e.target)}
+		on:keydown={e => e.key === 'Enter' && add(e.target)}
 	>
 
 	<div class='left'>