fix: use correct Datastar keydown event syntax

Replace invalid .key_enter and .enter modifiers with evt.key === 'Enter'
guard in the expression, per Datastar docs. Also fix __stop and __throttle
modifier syntax to use double underscores.

features/auth/pages/login.templ

@@ -20,7 +20,7 @@ templ LoginPage() {
 						type="text"
 						placeholder="Enter your username"
 					data-bind="username"
-					data-on:keydown.key_enter={ datastar.PostSSE("/auth/login") }
+					data-on:keydown={ "evt.key === 'Enter' && " + datastar.PostSSE("/auth/login") }
 					autofocus
 				/>
 					<label class="label" for="password">Password</label>
@@ -30,7 +30,7 @@ templ LoginPage() {
 						type="password"
 						placeholder="Enter your password"
 						data-bind="password"
-						data-on:keydown.key_enter={ datastar.PostSSE("/auth/login") }
+						data-on:keydown={ "evt.key === 'Enter' && " + datastar.PostSSE("/auth/login") }
 					/>
 				</fieldset>
 				<button

features/auth/pages/register.templ

@@ -20,7 +20,7 @@ templ RegisterPage() {
 						type="text"
 						placeholder="Choose a username"
 					data-bind="username"
-					data-on:keydown.key_enter={ datastar.PostSSE("/auth/register") }
+					data-on:keydown={ "evt.key === 'Enter' && " + datastar.PostSSE("/auth/register") }
 					autofocus
 				/>
 					<label class="label" for="password">Password</label>
@@ -30,7 +30,7 @@ templ RegisterPage() {
 						type="password"
 						placeholder="Choose a password (min 8 chars)"
 					data-bind="password"
-					data-on:keydown.key_enter={ datastar.PostSSE("/auth/register") }
+					data-on:keydown={ "evt.key === 'Enter' && " + datastar.PostSSE("/auth/register") }
 				/>
 					<label class="label" for="confirm">Confirm Password</label>
 					<input
@@ -39,7 +39,7 @@ templ RegisterPage() {
 						type="password"
 						placeholder="Confirm your password"
 						data-bind="confirm"
-						data-on:keydown.key_enter={ datastar.PostSSE("/auth/register") }
+						data-on:keydown={ "evt.key === 'Enter' && " + datastar.PostSSE("/auth/register") }
 					/>
 				</fieldset>
 				<button

features/common/components/shared.templ

@@ -28,7 +28,7 @@ templ NicknamePrompt(returnPath string) {
 					type="text"
 					placeholder="Enter your nickname"
 					data-bind="nickname"
-					data-on:keydown.key_enter={ datastar.PostSSE("%s", returnPath) }
+					data-on:keydown={ "evt.key === 'Enter' && " + datastar.PostSSE("%s", returnPath) }
 					required
 					autofocus
 				/>

features/lobby/pages/lobby.templ

@@ -73,7 +73,7 @@ templ LobbyPage(data LobbyData) {
 							placeholder="Enter your nickname"
 							data-bind="nickname"
 							required
-							data-on:keydown.enter={ datastar.PostSSE("/games") }
+							data-on:keydown={ "evt.key === 'Enter' && " + datastar.PostSSE("/games") }
 						/>
 					</fieldset>
 					<button

features/snakegame/pages/game.templ

@@ -34,7 +34,7 @@ templ GamePage(sg *snake.SnakeGame, mySlot int, messages []chat.Message, chatCfg
 			class="snake-wrapper flex flex-col items-center gap-4 p-4"
 			data-signals={ `{"chatMsg":""}` }
 			data-init={ datastar.GetSSE("/snake/%s/events", gameID) }
-			data-on:keydown.throttle_100ms={ keydownScript(gameID) }
+			data-on:keydown__throttle.100ms={ keydownScript(gameID) }
 			tabindex="0"
 		>
 			@GameContent(sg, mySlot, messages, chatCfg, gameID)