Migrate Installation to Effect with HttpClient for version fetching and
ChildProcessSpawner for package manager detection/upgrade. Register in
global ManagedRuntime. Split into effect.ts (service) and index.ts
(legacy adapters) to break the runtime circular dependency.
Rename AccountEffect → Account, AuthEffect → Auth,
TruncateEffect → Truncate to establish consistent naming where both
the effect.ts and index.ts files use the same namespace name.
Kit Langton
386eb03427