Custom self-update mechanism

[anfragment]

Description

There are some glaring issues with the current self-update setup:

• On macOS, go-github-selfupdate attempts to update the binary inside the Contents/MacOS folder, encountering permission errors. Replacing the entire .app file could resolve this issue.
• There is a hard dependency on GitHub. GitHub releases lack internationalization and generally offer less versatility in terms of how updates can be distributed.

Considering all of the above, the solution might look like this:

• A script that builds the application and creates a manifest file based on Git tags. The manifest can then be uploaded to an S3 bucket alongside build artifacts.
• A custom self-update module that replaces go-github-selfupdate.