fix: federated leaveSpace 403 and context menu for owner spaces

Use getMyUserIdForOrigin() in leaveSpace() so federated spaces send
the correct remote user ID instead of the home ID. Show context menu
for all spaces with "Invite People" action; "Leave Space" only for
non-owners.

packages/web/src/components/layout/SpaceSidebar.tsx

@@ -169,9 +169,11 @@ function SpaceContextMenu({ spaceId, x, y, onClose }: { spaceId: string; x: numb
   const space = useSpaceStore((s) => s.spaces.find(sp => sp.id === spaceId));
   const currentUserId = useAuthStore((s) => s.user?.id);
   const leaveSpace = useSpaceStore((s) => s.leaveSpace);
+  const generateInvite = useSpaceStore((s) => s.generateInvite);
   const currentSpaceId = useSpaceStore((s) => s.currentSpaceId);
   const setCurrentSpace = useSpaceStore((s) => s.setCurrentSpace);
   const setShowDms = useUIStore((s) => s.setShowDms);
+  const addToast = useUIStore((s) => s.addToast);
   const navigate = useNavigate();
 
   const isOwner = space?.ownerId === currentUserId;
@@ -198,12 +200,25 @@ function SpaceContextMenu({ spaceId, x, y, onClose }: { spaceId: string; x: numb
     };
   }, [onClose]);
 
-  // Don't render for owners (no menu items)
-  if (isOwner || !space) return null;
+  if (!space) return null;
+
+  const handleInvite = async () => {
+    try {
+      const code = await generateInvite(spaceId);
+      const origin = (space as any)._instanceOrigin || window.location.origin;
+      const url = `${origin}/invite/${code}`;
+      await navigator.clipboard.writeText(url);
+      addToast('Invite link copied to clipboard', 'success', 3000);
+    } catch {
+      addToast('Failed to generate invite', 'warning', 3000);
+    }
+    onClose();
+  };
 
   // Viewport-aware clamping
   const menuWidth = 180;
-  const menuHeight = 40;
+  const itemCount = isOwner ? 1 : 2;
+  const menuHeight = itemCount * 32 + 8;
   const clampedX = Math.min(x, window.innerWidth - menuWidth - 8);
   const clampedY = Math.min(y, window.innerHeight - menuHeight - 8);
 
@@ -214,22 +229,33 @@ function SpaceContextMenu({ spaceId, x, y, onClose }: { spaceId: string; x: numb
       style={{ left: clampedX, top: clampedY }}
     >
       <button
-        className="w-full flex items-center gap-2 px-3 py-1.5 text-sm text-accent-rose hover:bg-accent-rose/10 transition-colors"
-        onClick={() => {
-          if (currentSpaceId === spaceId) {
-            navigate('/channels/@me');
-            setCurrentSpace(null);
-            setShowDms(true);
-          }
-          leaveSpace(spaceId);
-          onClose();
-        }}
+        className="w-full flex items-center gap-2 px-3 py-1.5 text-sm text-txt-primary hover:bg-white/[0.06] transition-colors"
+        onClick={handleInvite}
       >
         <svg width="16" height="16" viewBox="0 0 24 24" fill="currentColor">
-          <path d="M10.09 15.59L11.5 17l5-5-5-5-1.41 1.41L12.67 11H3v2h9.67l-2.58 2.59zM19 3H5a2 2 0 00-2 2v4h2V5h14v14H5v-4H3v4a2 2 0 002 2h14c1.1 0 2-.9 2-2V5c0-1.1-.9-2-2-2z" />
+          <path d="M15 12c2.21 0 4-1.79 4-4s-1.79-4-4-4-4 1.79-4 4 1.79 4 4 4zm-9-2V7H4v3H1v2h3v3h2v-3h3v-2H6zm9 4c-2.67 0-8 1.34-8 4v2h16v-2c0-2.66-5.33-4-8-4z" />
         </svg>
-        Leave Space
+        Invite People
       </button>
+      {!isOwner && (
+        <button
+          className="w-full flex items-center gap-2 px-3 py-1.5 text-sm text-accent-rose hover:bg-accent-rose/10 transition-colors"
+          onClick={() => {
+            if (currentSpaceId === spaceId) {
+              navigate('/channels/@me');
+              setCurrentSpace(null);
+              setShowDms(true);
+            }
+            leaveSpace(spaceId);
+            onClose();
+          }}
+        >
+          <svg width="16" height="16" viewBox="0 0 24 24" fill="currentColor">
+            <path d="M10.09 15.59L11.5 17l5-5-5-5-1.41 1.41L12.67 11H3v2h9.67l-2.58 2.59zM19 3H5a2 2 0 00-2 2v4h2V5h14v14H5v-4H3v4a2 2 0 002 2h14c1.1 0 2-.9 2-2V5c0-1.1-.9-2-2-2z" />
+          </svg>
+          Leave Space
+        </button>
+      )}
     </div>,
     document.body,
   );

packages/web/src/stores/spaceStore.ts

@@ -239,7 +239,7 @@ export const useSpaceStore = create<SpaceState>((set, get) => ({
     const space = get().spaces.find(s => s.id === spaceId);
     const origin = (space as TaggedSpace)?._instanceOrigin ?? '';
     const targetApi = getApiForOrigin(origin);
-    const userId = useAuthStore.getState().user?.id;
+    const userId = getMyUserIdForOrigin(origin);
     if (!userId) return;
     await targetApi.spaces.removeMember(spaceId, userId);
     set((state) => ({