Package-level declarations

The MosaicLogger MosaicDependencyInjectionConfig.logger defaults to when an app doesn't supply its own — just println("$level: $msg"), no filtering beyond MosaicLogger's own level cutoff, no crash reporting, no remote sink. Meant for development; a real app typically supplies its own MosaicLogger wired to whatever telemetry/crash-reporting tool it already uses.

Log severity, ordered from most to least verbose — MosaicLogger.level is the minimum level that actually gets emitted; NONE as a logger's own MosaicLogger.level silences it entirely.

Logging abstraction every part of mosaic-client writes through — EventRunningScope.log/ logError, BuilderScope.log/logError, and every EventRunner's own error handling all eventually call into a MosaicLogger. Replaced app-wide via MosaicDependencyInjectionConfig.logger (defaults to DefaultMosaicLogger) — an app wiring its own crash-reporting/telemetry sink implements this once, and every log call in the framework (built-in or custom) routes through it automatically, with no per-call-site change needed.