feature: version one notification feature implemented.

backend/prisma/migrations/20260718120000_user_notifications/migration.sql

@@ -0,0 +1,41 @@
+-- CreateEnum
+CREATE TYPE "UserNotificationType" AS ENUM (
+  'CASE_SENT',
+  'CLINIC_COMMENT',
+  'LAB_COMMENT',
+  'LAB_COMMENT_CLINIC',
+  'CASE_IMPORTANT',
+  'TASK_COMPLETED',
+  'TASK_ASSIGNED',
+  'CONNECTION_REQUEST',
+  'STAFF_INVITE'
+);
+
+-- CreateTable
+CREATE TABLE "user_notifications" (
+  "id" TEXT NOT NULL,
+  "userId" TEXT NOT NULL,
+  "organizationId" TEXT NOT NULL,
+  "type" "UserNotificationType" NOT NULL,
+  "actorUserId" TEXT,
+  "payload" JSONB,
+  "href" TEXT NOT NULL,
+  "readAt" TIMESTAMP(3),
+  "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+  CONSTRAINT "user_notifications_pkey" PRIMARY KEY ("id")
+);
+
+CREATE INDEX "user_notifications_userId_organizationId_createdAt_idx"
+  ON "user_notifications"("userId", "organizationId", "createdAt");
+
+CREATE INDEX "user_notifications_userId_organizationId_readAt_idx"
+  ON "user_notifications"("userId", "organizationId", "readAt");
+
+ALTER TABLE "user_notifications"
+  ADD CONSTRAINT "user_notifications_userId_fkey"
+  FOREIGN KEY ("userId") REFERENCES "users"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+ALTER TABLE "user_notifications"
+  ADD CONSTRAINT "user_notifications_actorUserId_fkey"
+  FOREIGN KEY ("actorUserId") REFERENCES "users"("id") ON DELETE SET NULL ON UPDATE CASCADE;

backend/prisma/schema.prisma

@@ -30,6 +30,8 @@ model User {
   labCaseComments LabCaseComment[]
   labCaseActivities LabCaseActivity[]
   phoneVerificationCodes PhoneVerificationCode[]
+  userNotifications UserNotification[]
+  actedUserNotifications UserNotification[] @relation("UserNotificationActor")
 
   createdAt DateTime @default(now())
   updatedAt DateTime @updatedAt
@@ -435,6 +437,38 @@ enum LabCaseTabReadTarget {
   TREATMENT
 }
 
+enum UserNotificationType {
+  CASE_SENT
+  CLINIC_COMMENT
+  LAB_COMMENT
+  LAB_COMMENT_CLINIC
+  CASE_IMPORTANT
+  TASK_COMPLETED
+  TASK_ASSIGNED
+  CONNECTION_REQUEST
+  STAFF_INVITE
+}
+
+/// Fan-out inbox row per recipient. Independent of LabCaseActivity tab badges.
+model UserNotification {
+  id             String               @id @default(uuid())
+  userId         String
+  organizationId String
+  type           UserNotificationType
+  actorUserId    String?
+  payload        Json?
+  href           String
+  readAt         DateTime?
+  createdAt      DateTime             @default(now())
+
+  user      User  @relation(fields: [userId], references: [id], onDelete: Cascade)
+  actorUser User? @relation("UserNotificationActor", fields: [actorUserId], references: [id], onDelete: SetNull)
+
+  @@index([userId, organizationId, createdAt])
+  @@index([userId, organizationId, readAt])
+  @@map("user_notifications")
+}
+
 model LabCaseActivity {
   id          String              @id @default(uuid())
   labCaseId   String