feat: NCS-69 Challenge request (#3)

- create challange window
- challanges view page
- decline and accept
- notif tab (wip)
- active game window (wip)

---------

Co-authored-by: shahdlala66 <shahd.lala66@gmail.com>
Co-authored-by: Lala, Shahd <Shahd.Lala@sybit.de>
Reviewed-on: #3

src/app/models/challenge.models.ts

@@ -0,0 +1,49 @@
+export type ChallengeStatus = 'created' | 'pending' | 'accepted' | 'declined' | 'cancelled' | 'expired';
+
+export type PlayerColor = 'white' | 'black' | 'random';
+
+export interface Player {
+    id: string;
+    name: string;
+    rating: number;
+}
+
+export interface TimeControl {
+    type: string | null;
+    limit: number | null;
+    increment: number | null;
+}
+
+export interface Challenge {
+    id: string;
+    challenger: Player;
+    destUser: Player;
+    variant: string;
+    color: PlayerColor;
+    timeControl: TimeControl;
+    status: ChallengeStatus;
+    declineReason: string | null;
+    gameId: string | null;
+    expiresAt: string;
+    createdAt: string;
+}
+
+export interface SendChallengeRequest {
+    timeControl: {
+        limitSeconds: number;
+        incrementSeconds: number;
+    };
+    color?: PlayerColor;
+    ttlSeconds?: number;
+}
+
+export interface ListChallengesResponse {
+    'in'?: Challenge[];
+    'out'?: Challenge[];
+    incoming?: Challenge[];
+    outgoing?: Challenge[];
+}
+
+export interface DeclineChallengeRequest {
+    reason?: string;
+}