Add Prettier for TypeScript formatting

- Install prettier
- Configure .prettierrc.json and .prettierignore
- Add npm scripts: format, format:check
- Add Makefile target: format-frontend
- Format all frontend files

frontend/app/utils/appointment.ts

@@ -10,7 +10,7 @@ export interface StatusDisplay {
 
 /**
  * Get display information for an appointment status.
- * 
+ *
  * @param status - The appointment status string
  * @param isOwnView - If true, uses "Cancelled by you" instead of "Cancelled by user"
  */
@@ -25,9 +25,12 @@ export function getStatusDisplay(status: string, isOwnView: boolean = false): St
         textColor: "#f87171",
       };
     case "cancelled_by_admin":
-      return { text: "Cancelled by admin", bgColor: "rgba(239, 68, 68, 0.2)", textColor: "#f87171" };
+      return {
+        text: "Cancelled by admin",
+        bgColor: "rgba(239, 68, 68, 0.2)",
+        textColor: "#f87171",
+      };
     default:
       return { text: status, bgColor: "rgba(255,255,255,0.1)", textColor: "rgba(255,255,255,0.6)" };
   }
 }
-

frontend/app/utils/date.ts

@@ -17,8 +17,8 @@ export function formatDate(d: Date): string {
  */
 export function formatTime(isoString: string): string {
   const d = new Date(isoString);
-  return d.toLocaleTimeString("en-US", { 
-    hour: "2-digit", 
+  return d.toLocaleTimeString("en-US", {
+    hour: "2-digit",
     minute: "2-digit",
     hour12: false,
   });
@@ -81,4 +81,3 @@ export function isWeekend(date: Date): boolean {
   const day = date.getDay();
   return day === 0 || day === 6;
 }
-