Decor Sounds 0.7.15 beta - Share selected build

Builds now has a Share selected build button. Select your saved setup in the
list, then click Share selected build. If you have made changes, click Update
selected first. The export uses the saved build, not your current assignments.

Includes all saved room backgrounds, room effects and zones for that interior,
without requiring a room-by-room visit or filtering by old room-house mappings.
Preserves schedules, zone coordinates, height limits and background mute flags.
Uses the saved build name, house identifier and house background. Shows exported
room-background, room-effect and zone counts before copying.

Share current house remains available and is labelled as a visited-room-filtered
export. Selected-build export does not load or modify the selected build.

The existing visitor-pack format represents one interior OR one outdoor plot.
Mixed-scope builds are rejected with an explanation rather than silently trimmed.
A build saved without a house identifier must be loaded and updated in its house.
Personal game-audio policies, recovery drafts and library files are not published.
No Studio update is required for the existing schema-4 export format.

Includes New empty build from 0.7.14. No Musician or Total RP3 integration.

Validation: all shipped Lua files compile with Lua 5.1. Tests cover missing/stale
room mappings, complete saved assignments, schedules/heights, copy isolation,
saved-versus-active data, scope errors, JSON serialization and export counts.
Live UI and cloud publishing still need an in-game/end-to-end check.

INSTALL: Exit WoW and merge DecorSounds into Interface/AddOns, replacing matching
files. Keep DecorSoundsLibrary, Sounds/User and your WTF saved settings.
