[app] client-side cross-platform app management

[xendarboh]

Following: https://github.com/orgs/0KnowledgeNetwork/projects/1/views/1?pane=issue&itemId=55873525

Check these out for a client-side application:

• go-flutter-desktop: Flutter on Windows, MacOS and Linux - based on Flutter Embedding, Go and GLFW.
• hover: Hover helps developers to release Flutter applications on desktop.

Those cover desktop, then mobile app would be different on the wrapper framework side, still from the common go core.

From https://dox.eyeq.xyz/ArvIrrZKQx2HV9xucX8miw?view :

10. Scope & Supplement: Ultimately, the resulting client-side aspect will be installed/managed/upgraded as an application on end-user devices (with docs) and that may be out of scope of this task initially and deferred to a separate packaging task. However, initial implementation should be mindful of the target for cross-platform end-user deployments including Mac, Windows, Linux, Android, iOS, and Raspberry Pi. Desktops prioritized initially. Additional research and/or domain-expertise may be needed for packaging. In time, this application may relate to others with some shared functionality. Implementation options may include use of gomobile to compile Go code into Android and iOS libraries for use within a library-wrapping cross-platform framework (like Flutter) to ease development maintenance.

[xendarboh]

Build and release as a cli utility first, see: https://github.com/0KnowledgeNetwork/tmp-goreleaser/issues/4