feat(tenancy): add resend invitation for pending team members

New resend_invitation() service method regenerates the token and
resends the invitation email for pending members.

Available on all frontends:
- Merchant: POST /merchants/account/team/stores/{sid}/members/{uid}/resend
- Store: POST /store/team/members/{uid}/resend

UI: paper-airplane icon appears on pending members in both merchant
and store team pages.

i18n: resend_invitation + invitation_resent keys in 4 locales.
Also translated previously untranslated invitation_sent_successfully
in fr/de/lb.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/modules/tenancy/routes/api/merchant.py

@@ -299,6 +299,26 @@ async def merchant_team_update_role(
     return {"message": "Role updated successfully"}
 
 
+@_account_router.post("/team/stores/{store_id}/members/{user_id}/resend")
+async def merchant_team_resend_invitation(
+    store_id: int,
+    user_id: int,
+    current_user: UserContext = Depends(get_current_merchant_api),
+    merchant=Depends(get_merchant_for_current_user),
+    db: Session = Depends(get_db),
+):
+    """Resend invitation to a pending team member."""
+    from app.modules.tenancy.services.store_team_service import store_team_service
+
+    store = merchant_store_service.validate_store_ownership(db, merchant.id, store_id)
+    inviter = merchant_store_service.get_user(db, current_user.id)
+    result = store_team_service.resend_invitation(
+        db, store=store, user_id=user_id, inviter=inviter,
+    )
+    db.commit()
+    return result
+
+
 @_account_router.delete("/team/stores/{store_id}/members/{user_id}", status_code=204)
 async def merchant_team_remove_member(
     store_id: int,