Update Scala Toolkit to 0.4.0 & dynamically adjust Scala Native defaults

[Gedochao]

This PR does the following:

• bumps the default Scala Toolkit to 0.4.0
• lifts the Scala Native downgrade to 0.4.17 when default Scala toolkit is used (since toolkit 0.4.0 supports Scala Native 0.5.x)
• still downgrades Scla Native to 0.4.17 when default native version is used and the user explicitly uses Toolkit 0.3.0 or older

scala-cli -e 'println(os.pwd)' --toolkit 0.3.0 --native                          
# [warn] Scala Toolkit Version(0.3.0) does not support Scala Native 0.5.3, 0.4.17 should be used instead.
# [warn] Scala Native default version 0.5.3 is not supported in this build. Using 0.4.17 instead.
# Compiling project (Scala 3.4.2, Scala Native 0.4.17)
# Compiled project (Scala 3.4.2, Scala Native 0.4.17)
# [info] Linking (900 ms)
# [info] Checking intermediate code (quick) (63 ms)
# [info] Discovered 888 classes and 5298 methods
# [info] Optimizing (debug mode) (836 ms)
# [info] Generating intermediate code (620 ms)
# [info] Produced 10 files
# [info] Compiling to native code (1860 ms)
# [info] Linking with [pthread, dl]
# [info] Total (4406 ms)
/~/scala-cli-tests

It, however, does not:

• downgrade toolkit to 0.3.0 when built with Scala Native 0.4.x

scala-cli -e 'println(os.pwd)' --toolkit default --native --native-version 0.4.17
# Downloading 4 dependencies and 2 internal dependencies
# [error]  Error downloading org.scala-lang:toolkit-test_native0.4_3:0.4.0
# [error]   not found: /Users/pchabelski/.ivy2/local/org.scala-lang/toolkit-test_native0.4_3/0.4.0/ivys/ivy.xml
# [error]   not found: https://repo1.maven.org/maven2/org/scala-lang/toolkit-test_native0.4_3/0.4.0/toolkit-test_native0.4_3-0.4.0.pom
# [error]   not found: /Users/pchabelski/Library/Caches/ScalaCli/local-repo/1.3.2-12-70e34f/org.scala-lang/toolkit-test_native0.4_3/0.4.0/ivys/ivy.xml
# [error]   No fallback URL found
# [error] COMMAND_LINE
# [error]  Error downloading org.scala-lang:toolkit_native0.4_3:0.4.0
# [error]   not found: /Users/pchabelski/.ivy2/local/org.scala-lang/toolkit_native0.4_3/0.4.0/ivys/ivy.xml
# [error]   not found: https://repo1.maven.org/maven2/org/scala-lang/toolkit_native0.4_3/0.4.0/toolkit_native0.4_3-0.4.0.pom
# [error]   not found: /Users/pchabelski/Library/Caches/ScalaCli/local-repo/1.3.2-12-70e34f/org.scala-lang/toolkit_native0.4_3/0.4.0/ivys/ivy.xml
# [error]   No fallback URL found
# [error] COMMAND_LINE

Downgrading the default toolkit version when Scala Native 0.4.x is explicitly passed should be addressed separately (if we even decide to fix it, as that'd require rewriting a big chunk of the toolkit integration).

[kasiaMarek]

lgtm

[Gedochao]

Addresses the Scala Toolkit part of #2870