Sækja Haskell Stack 3.9.1

See https://haskellstack.org/ for installation and upgrade instructions.
Changes since v3.7.1:
Behavior changes:
- Where applicable and Stack supports the GHC version, only the wired-in packages of the actual version of GHC used are treated as wired-in packages.
- Stack now recognises ghc-internal as a GHC wired-in package.
- The configuration option package-index has a new default value: the keyids key lists the keys of the Hackage root key holders applicable from 2025-07-24.
- Stack's dot command now treats --depth the same way as the ls dependencies command, so that the nodes of stack dot --external --depth 0 are the same as the packages listed by stack ls dependencies --depth 0.
- When building GHC from source, on Windows, the default Hadrian build target is reloc-binary-dist and the default path to the GHC built by Hadrian is _build/reloc-bindist.
- Stack's haddock command no longer requires a package to have a main library that exposes modules.
- On Windows, the path segment platform\hash\ghc version, under .stack-work\install and .stack-work\hoogle, is hashed only once, rather than twice.
Other enhancements:
- Bump to Hpack 0.39.1.
- Consider GHC 9.14 to be a tested compiler and remove warnings.
- Consider Cabal 3.16 to be a tested library and remove warnings.
- From GHC 9.12.1, base is not a GHC wired-in package. In configuration files, the notify-if-base-not-boot key is introduced, to allow the exisitng notification to be muted if unwanted when using such GHC versions.
- Add flag --[no-]omit-this (default: disabled) to Stack's clean command to omit directories currently in use from cleaning (when --full is not specified).
- Add option -w as synonym for --stack-yaml.
- stack new now allows codeberg: as a service for template downloads
- In YAML configuration files, the compiler-target and compiler-bindist-path keys are introduced to allow, when building GHC from source, the Hadrian build target and Hadrian path to the built GHC to be specified.
Bug fixes:
- --PROG-option=<argument> passes --PROG-option=<argument> (and not --PROG-option="<argument>") to Cabal (the library).
- The message S-7151 now presents as an error, with advice, and not as a bug.
- Stack's dot command now uses a box to identify all GHC wired-in packages, not just those with no dependencies (being only rts).
- Stack's dot command now gives all nodes with no dependencies in the graph the maximum rank, not just those nodes with no relevant dependencies at all (being only rts, when --external is specified).
- Improved error messages for S-4634 and S-8215.
- Improved in-app help for the --hpack-force flag.
Thanks to all our contributors for this release:
- Alexey Kotlyarov
- Dino Morelli
- Jens Petersen
- Lauren Yim
- Mike Pilgrem
- Olivier Benz
- Simon Hengel
- Wolfram Kahl