Cabal and HLS should coordinate the cabal-version generated by cabal init

[fendor]

Describe the feature request

HLS is about to add support for .cabal files, displaying errors and warnings, offering completions, etc...

The .cabal file generated by cabal init has the latest available cabal-version.

For example:

> mkdir munihac-test 
> cd munihac-test 
> cabal-3.12.1.0 init -n --lib
> head -n 1 munihac-test.cabal
cabal-version:      3.12

This poses a problem for HLS, as HLS depends on ghc, we have to use the Cabal version linked against the ghc version the HLS binary supports. This means that the cabal-version produced by cabal init is by default virtually always newer than what any HLS version supports.

This leads to an ugly error message and most features not working in the hls-cabal-plugin :

My suggestion, after talking to @Kleidukos, is to coordinate the default cabal-version produced by cabal init with the support window of HLS. As the HLS-2.9.0.1 release supports GHC 9.4 - 9.10, we consequentially need the default cabal-version to be 3.6 (assuming, ghc-9.4 is linked against Cabal-3.6) for a better UX.

Additional context
HLS issue: haskell/haskell-language-server#4401

The issue is softened once private dependencies allow us to depend on a newer, private Cabal version for the cabal plugin: #9743