Selective-testing suites are planned from server history instead of booting every test bundle

The CLI no longer boots test bundles to enumerate suites while creating suite-granularity shard plans. It reads the module list from the built .xctestrun and asks the server to derive a per-module suite inventory from historical build data (per-branch first, default-branch fallback), with the final shard acting as a catch-all via -skip-testing for newly added or renamed suites. Plans no longer silently drop whole modules and no longer spend long stretches re-enumerating under simulator boot contention.