Auris v0.5.4

chore(brand): rename binary/package 3uxo → Auris (0.5.4) (#26)

Removes the «app-3uxo.exe» / «3uxo» artifacts:
- Cargo package app-3uxo → auris, lib app_3uxo_lib → auris_lib, main.rs, ci.yml,
  Cargo.lock. + mainBinaryName "Auris" → executable is now Auris.exe.
- Cosmetic: core crate description, README, LICENSE, npm package name, diagnostics
  header «Auris diagnostics» (+test).

Intentionally KEPT for update/data continuity (renaming breaks existing installs):
bundle identifier com.3uxo.app (app-data dir + updater identity), updater
endpoint / repo, 3uxo.db (user meetings DB), 3uxo.log, localStorage keys 3uxo.*.

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>