Migrate the satellite admin UI web app from the Svelte template used to
generate a Svelte App scaffolding to SvelteKit.
There aren't any functional changes in the application, however, the
commit has a lot because:
1. SvelteKit uses a different directory layout and constraints to it, so
the files have been moved.
2. The files have changed its formatting due to the new default linter
configurations that SvelteKit uses.
3. The linter detected some issues with using `object` and `any` types
in Typescript, so they have been replaced by better general types
(e.g. Record).
The migration allows to use the new tooling rather than Rollup
directly, besides that will empower the future of it when it needs more
features (e.g. different routes, etc.).
Change-Id: Ifa6736c13585708337f6c5a59388077b784eaddd
Change the satellite Admin HTTP server for:
* Embedding the UI assets into the Go binary.
* Serve the UI assets from the embedded file system or from a specific
directory path through a configuration flag, without requiring
authentication but keeping the authentication verification for the API
endpoints.
* Add tests to verify that the UI assets are served without
authentication.
Change-Id: I9003ac96f1ec585a189b67fc1cb315905403d557
Fix the Admin API endpoints when it response with a client error
response code.
The most of the client response error send a JSON body but the
`Content-Type` header wasn't set to the appropriated value. This commit
fixes them and it adds assertions to the tests to very the
`Content-Type` header.
Updates the README to briefly document about the format of the client
errors endpoints responses.
Change-Id: Ifaf2122def801701211438ce241046be1adc0e8c
