Add challenges preview + makefile

frontend/src/types/index.ts

@@ -104,6 +104,23 @@ export interface Challenge {
   created_at: string
 }
 
+export interface ChallengePreview {
+  game_id: number
+  game_title: string
+  title: string
+  description: string
+  type: string
+  difficulty: Difficulty
+  points: number
+  estimated_time: number | null
+  proof_type: ProofType
+  proof_hint: string | null
+}
+
+export interface ChallengesPreviewResponse {
+  challenges: ChallengePreview[]
+}
+
 // Assignment types
 export type AssignmentStatus = 'active' | 'completed' | 'dropped'