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.

chat/components/chat.templ

@@ -42,8 +42,7 @@ templ Chat(messages []chat.Message, cfg Config) {
 					placeholder="Chat..."
 					autocomplete="off"
 					data-bind="chatMsg"
-					data-on:keydown.stop=""
-				data-on:keydown.key_enter={ datastar.PostSSE("%s", cfg.PostURL) }
+					data-on:keydown__stop={ "evt.key === 'Enter' && " + datastar.PostSSE("%s", cfg.PostURL) }
 			/>
 		} else {
 			<input
@@ -51,7 +50,7 @@ templ Chat(messages []chat.Message, cfg Config) {
 				placeholder="Chat..."
 				autocomplete="off"
 				data-bind="chatMsg"
-				data-on:keydown.enter={ datastar.PostSSE("%s", cfg.PostURL) }
+				data-on:keydown={ "evt.key === 'Enter' && " + datastar.PostSSE("%s", cfg.PostURL) }
 			/>
 		}
 		<button