refactor: rename Audio Room → Nest project-wide

Aligns class names, package paths, string resource keys, UI text and
intent actions with the Nests branding used by the EGG specs in
nestsClient/specs/. Mechanical rename — no behavior change.

- Folders: audiorooms/ → nests/ (5 paths across amethyst, quartz)
- 30+ class renames (AudioRoom* → Nest*, AudioRooms* → Nests*)
- String resource keys audio_room_* → nest_*
- UI strings "Audio Room"/"Audio Rooms" → "Nest"/"Nests" (incl. all locales)
- Intent extras AUDIO_ROOM_* → NEST_*
- Compose route Route.AudioRooms → Route.Nests

Spec-aligned identifiers (MeetingSpaceEvent, meetingSpaces/, the nip53*
packages) are intentionally untouched — those are NIP-53 protocol
names, not "audio room" branding.

https://claude.ai/code/session_01RDpuki4t8StSg1CZcXnV5b

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/experimental/nests/admin/AdminCommandEventTest.kt

@@ -18,7 +18,7 @@
  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
-package com.vitorpamplona.quartz.experimental.audiorooms.admin
+package com.vitorpamplona.quartz.experimental.nests.admin
 
 import com.vitorpamplona.quartz.nip01Core.tags.aTag.ATag
 import kotlin.test.Test