Adds a "choose-type" step to the settings flow so users can pick between
Honcho Cloud (https://api.honcho.dev, API key required) and Self-Hosted
(URL + optional token) when creating a connection. Multi-instance support
already exists in the data layer, so cloud and self-hosted instances can
coexist.
- new HONCHO_CLOUD_URL constant and isCloudInstance helper in config.ts
- SettingsForm accepts a preset prop; cloud variant locks the endpoint
and enforces an API key
- InstancesManager gains a ConnectionTypeChooser entry point and renders
a Cloud icon for cloud instances in the list
- unit tests for both preset paths and cloud edit-mode detection
Replace single localStorage config with a named-instance store
({ instances: Instance[], activeId }). Adds an instances manager on
the settings page (list / add / edit / delete / activate) and a
sidebar switcher for quick swaps. Existing single-config users are
migrated transparently on first load.
Switching or deleting an instance clears the TanStack Query cache so
data from another deployment never bleeds into the active view.
