Define global version name

[wuan]

At the moment we use the following version name pattern:

• tags: v1.2.3
• versionName: v1.2.3

For Android (although the versionName is a free string) a typical SemVer pattern (like 1.2.3) is used in most cases. For F-Droid this is the default, which required some workarounds when bringing Destiny to F-Droid (see https://gitlab.com/fdroid/fdroiddata/-/merge_requests/12136).

The proposal is to reduce the versionName to be a clean SemVer string like 1.2.3. We will need to fix the code generating the link to the terms and condition but on the other Side our Android versioning will be clean. It might be worth to have a look at the version scheme which is typical used on the iOS side as well.

[donpui]

We could switch with next release.