Fixes#1327 - 'clawdbot message --channel telegram' fails with
'Unknown channel: telegram' because plugins weren't loaded.
The Commander code path (non-route-first) calls ensureConfigReady() in
preAction but doesn't load the plugin registry. Channel plugins like
telegram are registered during plugin loading, so getChannelPlugin()
returns undefined without it.
This adds ensurePluginRegistryLoaded() call for commands that need
channel plugin access: message, channels, directory.
Add shared parseBooleanValue()/isTruthyEnvValue() and apply across CLI, gateway, memory, and live-test flags for consistent env handling.
Introduce route-first fast paths, lazy subcommand registration, and deferred plugin loading to reduce CLI startup overhead.
Centralize config validation via ensureConfigReady() and add config caching/deferred shell env fallback for fewer IO passes.
Harden logger initialization/imports and add focused tests for argv, boolean parsing, frontmatter, and CLI subcommands.
