Vamooses Neighbors

### Added
- Friendly messages for more housing visit failure codes on the reservation path
  (ActionLockedByCombat, HouseEditLockFailed, LockedByOtherPlayer,
  LockOperationFailed, MissingExpansionAccess, TimerunningNotAllowed,
  UnlockOperationFailed); previously these fell through to silent or generic
  failure text

### Fixed
- Eliminated root cause of ADDON_ACTION_BLOCKED Button:Hide() taints during
  combat refreshes in Browse and Directory tabs. Previously each row carried its
  own SecureActionButtonTemplate child, which permanently promoted the row's
  parent Button to "protected" and caused the scrollbox pool's Release/Hide to
  be blocked in combat. Now a single floating secure visit button lives at
  UIParent scope and repositions over the hovered row; no protected frames
  exist inside the scrollbox row pool anymore, so pool churn during combat
  (BNet/guild scanner completing mid-fight, neighborhood list updates,
  scrolling) is fully safe. The visit action appears on hover for friend/guild
  houses and recent visits; player-owned plots and vacant plots retain their
  existing non-secure buttons unchanged.
- Fixed guild house scan crashing inside houses, delves, dungeons, raids, and
  arenas with "bad argument #1 to 'ipairs' (table expected, got secret)".
  C_Club.GetSubscribedClubs returns opaque secret values in protected contexts;
  FetchGuildHouses now defers until the player steps outdoors and retries
  automatically on ZONE_CHANGED_INDOORS / ZONE_CHANGED_NEW_AREA.

### Changed
- Replaced the "Last full scan: Xh ago" label on the Friends/Guild subtabs with
  a session-accurate status: "House keys current" (dim) when a full scan has
  completed in the current WoW client process, or "House keys expired"
  (orange) when it hasn't. houseGUIDs are server-issued session tokens that
  reset every time the client restarts, so a timestamp from a prior session is
  misleading -- the cached data is stale regardless of how recent it looks.
  The new label tells you exactly what matters: can you click Visit right now
  and expect it to work.