Add killerName to Mission model and enhance overlay components

- Introduced killerName field in the Mission model within the Prisma schema and created a corresponding migration.
- Updated mission management logic to assign a killerName during mission creation.
- Enhanced overlay components to display killer information, including avatar and name, in both expanded and minimized panels.
- Added new CSS styles for killer display in the overlay.
- Included new avatar images for various killers in the overlay assets.

libs/api-interfaces/src/lib/mission.ts

@@ -31,6 +31,7 @@ export const MissionSchema = z.object({
   difficulty: z.number().int().min(1).max(3),
   durationMinutes: MissionDurationMinutesSchema.default(20),
   status: MissionStateSchema,
+  killerName: z.string().optional(),
   encounterLibraryVersion: z.string().min(1),
   nextTickAt: z.iso.datetime(),
   tickIndex: z.number().int().min(0),