fix: use format string for datastar.PostSSE in chat component

PostSSE requires a constant format string; pass "%s" with the URL
as an argument instead of passing the URL directly.

chat/components/chat.templ

@@ -43,20 +43,20 @@ templ Chat(messages []chat.Message, cfg Config) {
 					autocomplete="off"
 					data-bind="chatMsg"
 					data-on:keydown.stop=""
-					data-on:keydown.key_enter={ datastar.PostSSE(cfg.PostURL) }
-				/>
-			} else {
-				<input
-					type="text"
-					placeholder="Chat..."
-					autocomplete="off"
-					data-bind="chatMsg"
-					data-on:keydown.enter={ datastar.PostSSE(cfg.PostURL) }
-				/>
-			}
-			<button
-				type="button"
-				data-on:click={ datastar.PostSSE(cfg.PostURL) }
+				data-on:keydown.key_enter={ datastar.PostSSE("%s", cfg.PostURL) }
+			/>
+		} else {
+			<input
+				type="text"
+				placeholder="Chat..."
+				autocomplete="off"
+				data-bind="chatMsg"
+				data-on:keydown.enter={ datastar.PostSSE("%s", cfg.PostURL) }
+			/>
+		}
+		<button
+			type="button"
+			data-on:click={ datastar.PostSSE("%s", cfg.PostURL) }
 			>
 				Send
 			</button>