v0.5.8

Gem-only revision atop upstream core v0.5.7. Published to RubyGems: https://rubygems.org/gems/microsandbox-rb/versions/0.5.8

Added

• Registry authentication on Sandbox.create: registry_auth: { username:, password: } (password may be a token) for private/authenticated registries and to lift Docker Hub's anonymous rate limit, plus registry_insecure: (plain HTTP) and registry_ca_certs: (PEM String/Array) for self-hosted registries. Without it, the core's default resolution (OS keyring, global config, ~/.docker/config.json) still applies.
• Microsandbox.ensure_runtime! — provisions msb + libkrunfw on first use (called automatically by Sandbox.create/start), making precompiled platform gems usable without a manual install step. Opt out via MICROSANDBOX_NO_AUTO_INSTALL.
• Plus the accumulated alignment surface: async lifecycle (request_stop/request_kill/request_drain/wait_until_stopped/detach/owns_lifecycle?), list_with, all_sandbox_metrics, streaming metrics_stream/log_stream, snapshots, and expanded create options.

Changed

• cross-gems release job installs libcap-ng-dev:arm64 via Debian multiarch for the aarch64-linux cross-build; corrected the precompiled-gem cross-compile docs. Precompiled gems remain workflow_dispatch-only, promoted manually after per-platform validation.

See CHANGELOG.md for full details.