Switch from nickel to haskell.nix

Author: neilmayhew

.envrc

@@ -1,2 +1,4 @@
-watch_file project.ncl
-use flake
+# shellcheck shell=bash
+if has nix; then
+  use flake
+fi

.gitignore

@@ -2,4 +2,7 @@
 
 .devenv
 dist-newstyle
-.vscode
+.vscode
+
+/.pre-commit-config.yaml
+/result

cuddle.cabal

@@ -21,7 +21,7 @@ copyright: 2025 Input Output Global Inc (IOG)
 category: Codec
 build-type: Simple
 extra-doc-files: CHANGELOG.md
-tested-with: ghc =={9.6, 9.8, 9.10, 9.12}
+tested-with: ghc ==9.6 || ==9.8 || ==9.10 || ==9.12
 
 source-repository head
   type: git
@@ -38,8 +38,7 @@ flag example
   default: False
 
 common warnings
-  ghc-options:
-    -Wall
+  ghc-options: -Wall
 
 library
   import: warnings