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.

apps/api/prisma/migrations/20260511000000_add_mission_killer_name/migration.sql

@@ -0,0 +1,2 @@
+-- AlterTable
+ALTER TABLE "missions" ADD COLUMN "killer_name" TEXT;

apps/api/prisma/schema.prisma

@@ -39,6 +39,7 @@ model Mission {
   difficulty              Int                  @db.SmallInt
   durationMinutes         Int                  @default(20) @map("duration_minutes") @db.SmallInt
   status                  String               @default("active")
+  killerName              String?              @map("killer_name")
   encounterLibraryVersion String               @map("encounter_library_version")
   startedAt               DateTime             @default(now()) @map("started_at")
   endedAt                 DateTime?            @map("ended_at")

apps/api/src/app/missions/encounter.service.ts

@@ -79,7 +79,7 @@ export class EncounterService {
 
       const libEncounter = getEncounterById(encounter.key);
       const flavor = libEncounter
-        ? pickFlavor(libEncounter, { success: result.success }, rng)
+        ? pickFlavor(libEncounter, { success: result.success, killerName: mission.killerName }, rng)
         : result.logText;
 
       newLog.push({ ...result, logText: flavor });

apps/api/src/app/missions/missions.service.ts

@@ -10,7 +10,8 @@ import type {
   Survivor,
   SurvivorStats,
 } from '@fog-explorer/api-interfaces';
-import { getLibraryVersion } from '@fog-explorer/encounter-library';
+import { getLibraryVersion, KILLER_NAMES } from '@fog-explorer/encounter-library';
+import seedrandom = require('seedrandom');
 import { TwitchJwtPayload } from '../auth/twitch-jwt.guard';
 import { PrismaService } from '../prisma/prisma.service';
 import { MissionStoreService } from './mission-store.service';
@@ -38,6 +39,7 @@ export class MissionsService {
     const nextTickAt = new Date(now.getTime() + TICK_BASE_INTERVAL_MS + jitter);
     const stats: SurvivorStats = { objectives: 5, survival: 5, altruism: 5 };
     const survivorName = characterName ?? defaultName(claims.opaque_user_id);
+    const killerName = pickKiller(missionId);
 
     // Upsert user and create survivor + mission in one transaction.
     await this.prisma.$transaction(async (tx) => {
@@ -66,6 +68,7 @@ export class MissionsService {
           difficulty,
           durationMinutes,
           status: 'active',
+          killerName,
           encounterLibraryVersion: getLibraryVersion(),
           nextTickAt,
           participants: {
@@ -98,6 +101,7 @@ export class MissionsService {
       difficulty,
       durationMinutes,
       status: 'active',
+      killerName,
       encounterLibraryVersion: getLibraryVersion(),
       nextTickAt: nextTickAt.toISOString(),
       tickIndex: 0,
@@ -154,3 +158,8 @@ export class MissionsService {
 function defaultName(opaqueUserId: string): string {
   return `Survivor ${opaqueUserId.slice(-4)}`;
 }
+
+function pickKiller(missionId: string): string {
+  const rng = seedrandom(`killer:${missionId}`);
+  return KILLER_NAMES[Math.floor(rng() * KILLER_NAMES.length)];
+}