feat(team): proper member removal + self-leave flow

Member-management UX cleanup:

- Replaced window.confirm() with shadcn Dialog confirmation (matches
  every other destructive action in the app).
- Toast feedback on success/error for both removal and role updates —
  before, errors from the server (örn. 'Sahibi yalnızca başka bir sahip
  kaldırabilir') were swallowed.
- New 'Ayrıl' (leave) button on the current user's own row — previously
  there was no way for a member to leave a workspace except by being
  removed by an admin.

Server (lib/appwrite/team-actions.ts):
- New leaveWorkspaceAction:
  * Refuses if the caller is the only owner (would leave the workspace
    ownerless).
  * Calls teams.deleteMembership for the caller's own membership.
  * Clears account.prefs.activeTenant + isletmem-tenant cookie so the
    next request goes to fallback tenant or onboarding.
  * Audit-logged with self:true marker.
- removeMemberAction unchanged (already had owner-only-can-remove-owner
  + can't-remove-self guards).

UI:
- Each row's action cell now shows: 'Ayrıl' (self) / 'Çıkar' (others, if
  canManage and target isn't owner) / nothing (the rest).
- Removal dialog explains data isn't deleted, just access revoked.
- Leave dialog warns the user about losing access.
- Both dialogs gate close-on-outside-click while a request is in flight.

src/app/(dashboard)/settings/members/components/members-table.tsx

@@ -1,11 +1,21 @@
 "use client";
 
+import { useRouter } from "next/navigation";
 import { useState, useTransition } from "react";
-import { Loader2, Trash2 } from "lucide-react";
+import { DoorOpen, Loader2, Trash2 } from "lucide-react";
+import { toast } from "sonner";
 
 import { Badge } from "@/components/ui/badge";
 import { Button } from "@/components/ui/button";
 import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
+import {
+  Dialog,
+  DialogContent,
+  DialogDescription,
+  DialogFooter,
+  DialogHeader,
+  DialogTitle,
+} from "@/components/ui/dialog";
 import {
   Select,
   SelectContent,
@@ -21,7 +31,11 @@ import {
   TableHeader,
   TableRow,
 } from "@/components/ui/table";
-import { removeMemberAction, updateMemberRoleAction } from "@/lib/appwrite/team-actions";
+import {
+  leaveWorkspaceAction,
+  removeMemberAction,
+  updateMemberRoleAction,
+} from "@/lib/appwrite/team-actions";
 
 type Member = {
   id: string;
@@ -51,34 +65,59 @@ export function MembersTable({
   isOwner: boolean;
   canManage: boolean;
 }) {
+  const router = useRouter();
   const [busy, setBusy] = useState<string | null>(null);
   const [, startTransition] = useTransition();
+  const [removing, setRemoving] = useState<Member | null>(null);
+  const [leaving, setLeaving] = useState(false);
 
   const setRole = (membershipId: string, role: string) => {
     setBusy(membershipId);
     startTransition(async () => {
-      const fd = new FormData();
-      fd.set("membershipId", membershipId);
-      fd.set("role", role);
-      await updateMemberRoleAction({ ok: false }, fd);
+      const result = await updateMemberRoleAction({ ok: false }, formDataFor({
+        membershipId,
+        role,
+      }));
+      if (result.ok) toast.success("Rol güncellendi.");
+      else toast.error(result.error ?? "Rol güncellenemedi.");
       setBusy(null);
     });
   };
 
-  const remove = (membershipId: string, name: string) => {
-    if (!confirm(`${name} adlı üyeyi çalışma alanından çıkarmak istediğinize emin misiniz?`)) {
-      return;
-    }
-    setBusy(membershipId);
+  const handleRemove = () => {
+    if (!removing) return;
+    setBusy(removing.id);
     startTransition(async () => {
-      const fd = new FormData();
-      fd.set("membershipId", membershipId);
-      await removeMemberAction({ ok: false }, fd);
+      const result = await removeMemberAction({ ok: false }, formDataFor({
+        membershipId: removing.id,
+      }));
+      if (result.ok) {
+        toast.success(`${removing.name} ekipten çıkarıldı.`);
+        setRemoving(null);
+      } else {
+        toast.error(result.error ?? "İşlem başarısız.");
+      }
+      setBusy(null);
+    });
+  };
+
+  const handleLeave = () => {
+    setBusy("leave");
+    startTransition(async () => {
+      const result = await leaveWorkspaceAction();
+      if (result.ok) {
+        toast.success("Çalışma alanından ayrıldınız.");
+        setLeaving(false);
+        router.push("/dashboard");
+      } else {
+        toast.error(result.error ?? "Ayrılma başarısız.");
+      }
       setBusy(null);
     });
   };
 
   return (
+    <>
       <Card>
         <CardHeader>
           <CardTitle>Üyeler ({members.length})</CardTitle>
@@ -130,13 +169,30 @@ export function MembersTable({
                       )}
                     </TableCell>
                     <TableCell className="text-right">
-                    {canManage && !isSelf && !isMemberOwner ? (
+                      {isSelf ? (
                         <Button
                           type="button"
                           variant="ghost"
                           size="sm"
+                          className="text-muted-foreground"
+                          disabled={busy === "leave"}
+                          onClick={() => setLeaving(true)}
+                        >
+                          {busy === "leave" ? (
+                            <Loader2 className="size-3.5 animate-spin" />
+                          ) : (
+                            <DoorOpen className="size-3.5" />
+                          )}
+                          Ayrıl
+                        </Button>
+                      ) : canManage && !isMemberOwner ? (
+                        <Button
+                          type="button"
+                          variant="ghost"
+                          size="sm"
+                          className="text-destructive hover:text-destructive"
                           disabled={busy === m.id}
-                        onClick={() => remove(m.id, m.name)}
+                          onClick={() => setRemoving(m)}
                         >
                           {busy === m.id ? (
                             <Loader2 className="size-3.5 animate-spin" />
@@ -154,5 +210,77 @@ export function MembersTable({
           </Table>
         </CardContent>
       </Card>
+
+      <Dialog
+        open={Boolean(removing)}
+        onOpenChange={(v) => !v && busy === null && setRemoving(null)}
+      >
+        <DialogContent>
+          <DialogHeader>
+            <DialogTitle>Üyeyi ekipten çıkar</DialogTitle>
+            <DialogDescription>
+              {removing && (
+                <>
+                  <strong>{removing.name}</strong> ({removing.email}) ekipten çıkarılacak.
+                  Verileri silinmez ama bu çalışma alanına erişimi kalkar.
+                </>
+              )}
+            </DialogDescription>
+          </DialogHeader>
+          <DialogFooter>
+            <Button
+              variant="outline"
+              onClick={() => setRemoving(null)}
+              disabled={busy !== null}
+            >
+              Vazgeç
+            </Button>
+            <Button
+              variant="destructive"
+              onClick={handleRemove}
+              disabled={busy !== null}
+            >
+              {busy ? <Loader2 className="size-4 animate-spin" /> : <Trash2 className="size-4" />}
+              Çıkar
+            </Button>
+          </DialogFooter>
+        </DialogContent>
+      </Dialog>
+
+      <Dialog open={leaving} onOpenChange={(v) => !v && busy === null && setLeaving(false)}>
+        <DialogContent>
+          <DialogHeader>
+            <DialogTitle>Çalışma alanından ayrıl</DialogTitle>
+            <DialogDescription>
+              Bu çalışma alanındaki tüm verilere erişiminiz kalkar. Tekrar davet edilmedikçe
+              giremezsiniz. Devam etmek istediğinize emin misiniz?
+            </DialogDescription>
+          </DialogHeader>
+          <DialogFooter>
+            <Button
+              variant="outline"
+              onClick={() => setLeaving(false)}
+              disabled={busy !== null}
+            >
+              Vazgeç
+            </Button>
+            <Button
+              variant="destructive"
+              onClick={handleLeave}
+              disabled={busy !== null}
+            >
+              {busy ? <Loader2 className="size-4 animate-spin" /> : <DoorOpen className="size-4" />}
+              Ayrıl
+            </Button>
+          </DialogFooter>
+        </DialogContent>
+      </Dialog>
+    </>
   );
 }
+
+function formDataFor(fields: Record<string, string>): FormData {
+  const fd = new FormData();
+  for (const [k, v] of Object.entries(fields)) fd.set(k, v);
+  return fd;
+}

src/lib/appwrite/team-actions.ts

@@ -244,6 +244,74 @@ export async function removeMemberAction(
   return { ok: true };
 }
 
+/**
+ * Self-leave: the current user removes themselves from the active tenant.
+ * - If they're the only owner, the call is refused (would leave the workspace
+ *   ownerless).
+ * - On success the active-tenant cookie + prefs.activeTenant are cleared so
+ *   the next request goes through fallback to another team or onboarding.
+ */
+export async function leaveWorkspaceAction(): Promise<MemberActionState> {
+  let ctx;
+  try {
+    ctx = await requireTenant();
+  } catch {
+    return { ok: false, error: "Yetkiniz yok." };
+  }
+
+  try {
+    const admin = createAdminClient();
+    const memberships = await admin.teams.listMemberships(ctx.tenantId);
+    const me = memberships.memberships.find((m) => m.userId === ctx.user.id);
+    if (!me) return { ok: false, error: "Üyelik bulunamadı." };
+
+    if (me.roles.includes("owner")) {
+      const otherOwners = memberships.memberships.filter(
+        (m) => m.userId !== ctx.user.id && m.roles.includes("owner"),
+      );
+      if (otherOwners.length === 0) {
+        return {
+          ok: false,
+          error:
+            "Tek sahip olduğunuz için ayrılamazsınız. Önce başka bir üyeyi sahip yapın.",
+        };
+      }
+    }
+
+    await admin.teams.deleteMembership(ctx.tenantId, me.$id);
+
+    await logAudit({
+      tenantId: ctx.tenantId,
+      userId: ctx.user.id,
+      action: "delete",
+      entityType: "membership",
+      entityId: me.$id,
+      changes: { self: true, userEmail: ctx.user.email },
+    });
+
+    // Clear active-tenant pointers so the user lands somewhere safe next request.
+    try {
+      const session = await createSessionClient();
+      const user = await session.account.get();
+      const prefs = { ...(user.prefs as Record<string, unknown>) };
+      delete prefs.activeTenant;
+      await session.account.updatePrefs(prefs);
+    } catch {
+      /* ignore */
+    }
+    try {
+      (await cookies()).delete(ACTIVE_TENANT_COOKIE);
+    } catch {
+      /* ignore */
+    }
+  } catch (e) {
+    return { ok: false, error: appwriteError(e) };
+  }
+
+  revalidatePath("/", "layout");
+  return { ok: true };
+}
+
 export async function updateMemberRoleAction(
   _prev: MemberActionState,
   formData: FormData,