feat(pm): add bug-report button with screenshot annotation and admin panel

- New BugReport MongoDB model (comment, contact, userId, screenshot, pmState, status)
- POST /api/bug-reports — authenticated submit; emails emanuel@faktorxmensch.com on receipt
- GET/PATCH /api/admin/bug-reports + /[id] — admin list, detail with screenshot, status toggle
- /pm: "Bug" button in HUD captures viewport screenshot (html2canvas), shows annotation
  canvas where testers can draw arrows; submits comment + contact + state snapshot
- /admin: new "Bug Reports" tab with open-count badge, screenshot expand, "Erledigt" toggle,
  and "In /pm öffnen" link that restores captured engine state via ?restoreBugReport=<id>

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

server/models/BugReport.ts

@@ -0,0 +1,45 @@
+import mongoose from 'mongoose'
+
+export type BugReportStatus = 'open' | 'resolved'
+
+export interface PmStateSnapshot {
+  flowSlug?: string
+  scenarioId?: string
+  currentStateId?: string
+  variables?: Record<string, any>
+  flags?: Record<string, boolean>
+  flightContext?: Record<string, any>
+  communicationLog?: any[]
+}
+
+export interface BugReportDocument extends mongoose.Document {
+  comment: string
+  contact: string
+  userId?: mongoose.Types.ObjectId
+  screenshot?: string
+  pmState?: PmStateSnapshot
+  status: BugReportStatus
+  createdAt: Date
+}
+
+const bugReportSchema = new mongoose.Schema<BugReportDocument>({
+  comment: { type: String, required: true, trim: true, maxlength: 4000 },
+  contact: { type: String, required: true, trim: true, maxlength: 200 },
+  userId: { type: mongoose.Schema.Types.ObjectId, ref: 'User', index: true },
+  screenshot: { type: String },
+  pmState: {
+    flowSlug: { type: String },
+    scenarioId: { type: String },
+    currentStateId: { type: String },
+    variables: { type: mongoose.Schema.Types.Mixed, default: {} },
+    flags: { type: mongoose.Schema.Types.Mixed, default: {} },
+    flightContext: { type: mongoose.Schema.Types.Mixed, default: {} },
+    communicationLog: { type: [mongoose.Schema.Types.Mixed], default: [] },
+  },
+  status: { type: String, enum: ['open', 'resolved'], default: 'open', index: true },
+  createdAt: { type: Date, default: () => new Date(), index: true },
+})
+
+export const BugReport =
+  (mongoose.models.BugReport as mongoose.Model<BugReportDocument> | undefined) ||
+  mongoose.model<BugReportDocument>('BugReport', bugReportSchema)