Fix SBT IO version compatibility issue

[tiborrr]

Problem

The project was experiencing build issues due to version mismatches between SBT 1.10.7 and sbt-io dependencies. This was causing compatibility problems, particularly when using sbt-native-packager and sbt-github-pages plugins together with sbt-bloop.

Solution

Implemented the same version resolution strategy that SBT itself uses in their codebase. https://github.com/sbt/sbt/blob/1.10.x/project/Dependencies.scala
This allows for:

• Flexible version resolution through environment variables
• Fallback to a known working version (1.10.3)
• Better compatibility with SBT plugins

Changes

• Modified project/build.sbt to use SBT's version resolution strategy
• Added fallback to sbt-io 1.10.3 which is known to be stable and published
• Maintained compatibility with existing plugins