lib/types: init defaultComposedFunctor for types.{attrsWith,listOf}

[hsjobeki]

Overall i think all types.functor should deprecate functor.wrapped

This PR introduces a new defaultFunctor for composed types that makes the migration easy.

Additional thoughts:

types should be constructible via type payload maybe we want to spread the {type}With payload pattern ?
This design thought also went into the default functor:

Compare:

• attrsWith
• listWith (doesnt exist)
• submoduleWith
• deferredModuleWith
• stringWith (doesnt exist)
• ...

This only internally changes the following for now.

• listOf requires overriding the type because there is no listWith yet.
• attrsWith doesn't require any additional attribute overrides. (Only the custom binOp for merging)

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 25.05 Release Notes (or backporting 24.11 and 25.05 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md.

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[infinisil]

Discussed this together in a meeting with @hsjobeki:

• This should only be an internal refactoring, no new function should be exposed
• The function can be specific to an elemType payload, e.g. elemTypeFunctor, which can then also implement the merge for elemType specifically
• The deprecation message makes sense to have for types that currently use wrapped

In the future we could also imagine an interface like this for creating types with appropriate functors more easily:

submoduleWith = createAttrType {
  # Doesn't need to stay in sync with `submoduleWith` anymore
  # because the name is decoupled from the `lib.types` identifier
  name = "submodule";
  payloadSpec = {
    modules = {
      # No default, required argument
      binOp = a: b: a ++ b;
    };
    specialArgs = {
      default = {};
      binOp = unionOfDisjoint;
    }
    # ...
  };
  # Gets a functor/typeMerge based on the above spec
  create = { modules, specialArgs }: mkOptionType {
    description = "...";
    merge = "...";
    # ...
  };
};

[infinisil]

Reviewed and updated together in a meeting with @hsjobeki, looking good now!