feat: activity assignment + team view for owner/admin

db: activities.assigneeId column (string, optional)

activity-actions: assigneeId saved on create (default: self), cleared on update
validation: assigneeId added to activitySchema
schema: assigneeId field on Activity type

activity-form-sheet: Atanan Kişi dropdown for owner/admin with member list
activity-team-view: new component — activities grouped by assignee,
  completion/edit/delete actions, overdue indicator, member avatars
activities-client: Ekip tab (owner/admin only), members + currentUserId props
activities page: fetches team memberships + user details, passes to client
activity-email-actions: filter by assigneeId ?? createdBy for both me/team modes

src/app/(dashboard)/activities/page.tsx

@@ -11,9 +11,9 @@ import { ActivitiesClient } from "@/components/activities/activities-client";
 
 export default async function ActivitiesPage() {
   const ctx = await requireTenant();
-  const { tablesDB } = createAdminClient();
+  const { tablesDB, teams, users } = createAdminClient();
 
-  const [customers, properties, activitiesResult] = await Promise.all([
+  const [customers, properties, activitiesResult, membershipsResult] = await Promise.all([
     listCustomers(ctx.tenantId),
     listProperties(ctx.tenantId),
     tablesDB.listRows({
@@ -25,10 +25,22 @@ export default async function ActivitiesPage() {
         Query.limit(300),
       ],
     }),
+    teams.listMemberships(ctx.tenantId),
   ]);
 
   const activities = JSON.parse(JSON.stringify(activitiesResult.rows)) as Activity[];
 
+  const members = (
+    await Promise.all(
+      membershipsResult.memberships
+        .filter((m) => m.userId && m.confirm)
+        .map(async (m) => {
+          const u = await users.get(m.userId).catch(() => null);
+          return u ? { id: m.userId, name: u.name } : null;
+        }),
+    )
+  ).filter((m): m is { id: string; name: string } => m !== null);
+
   return (
     <div className="flex flex-1 flex-col gap-4 p-4 md:p-6">
       <ActivitiesClient
@@ -36,6 +48,8 @@ export default async function ActivitiesPage() {
         customers={customers}
         properties={properties}
         role={ctx.role}
+        members={members}
+        currentUserId={ctx.user.id}
       />
     </div>
   );