* Refactor buildIdris slightly and support installing libraries with source. Add the Idris2 API package as an output of the flake.
* update templates and simplify construction of a search path.
* use newer method of specifying default package
* swap out trace function for warn function. fix warnings in template generation
- `idris2 --version` correctly displays hash again
- `idris2 --install <ipkg>` defaults to $HOME/idris2 instead of a
literal `~/.idris2`.
- allows building in Nix on latest MacOS
This allows for cross-flake testing of content-addressible nix derivations without
affecting other users of the flake (which would be the cases if CA-drvs would be
hard-coded upstream) and without losing the ability to quickly update to the latest
idris2 version (which would happen if a fork of the repo would be used).
See also: https://discourse.nixos.org/t/content-addressed-nix-call-for-testers/12881
The flake can still be used as usual, but it will gain an output `overrideOptions`, which can be used like e.g.
```nix
let
idrisx = idris.overrideOptions {
config.contentAddressedByDefault = true;
};
in { ... }
```
* Add utility functions to treat All as a heterogeneous container
* Distinguish RefC Int and Bits types
* Change RefC Integers to be arbitrary precision
* Add RefC Bits maths operations
* Make RefC div and mod Euclidean
* Add RefC bit-ops tests
* Add RefC integer comparison tests
* Add RefC IntN support
