Cardano Updates

Currently, the `B` constructor contains a `ByteString` (pinned in
memory) with a max length of 64 bytes. Since the `ByteString` is small
and can be instantiated frequently, it makes more sense to use an
unpinned byte array representation (`Data.Array.Byte.ByteArray`) so
that we can take advantage of Haskell's garbage collection to improve
memory allocation of objects in the heap.

We also place an upper bound on `nothunks` because of new orphan
instance (`instance NoThunks ByteArray`) that is going to be upstreamed.

Add `NoThunks` instances for primitive, storable and strict boxed Vectors.

Strict boxed Vectors were added in `v0.13.2` of the `vector` package.

Tested with:

```
> cabal build -f vector
> cabal build -f -vector
> cabal build --constraint="vector < 0.13.2"
```

This requires a new era (Conway -> Dijkstra), not an intra-era HF

Signed-off-by: cryptodj413 <[email protected]>

Signed-off-by: cryptodj413 <[email protected]>

Signed-off-by: cryptodj413 <[email protected]>

Remove default implementation of `fromPlutusData` in `ToPlutusData` typeclass

* fix: replace builtins.appendContext with context-carrying concatenation

builtins.appendContext validates that store paths exist locally, which
fails when paths come from flake inputs that aren't available on the
evaluating machine (e.g. CHaP in cardano-node builds).

Instead, preserve string context through parsing by using
builtins.substring 0 0 to capture context from input strings and
re-attach it via concatenation after builtins.match/split strip it.

- parseBlockLines: carry context from input lines to parsed attr values
- parseSourceRepositoryPackages: carry context through builtins.split
- extractSourceRepoPackageData: use unsafeDiscardStringContext for
  sha256map attribute name lookups
- parseRepositoryBlock: remove addContext helper that used appendContext,
  use attrs.url directly (context now preserved by parseBlockLines)
- call-cabal-project-to-nix: remove appendContext on writeText, export
  rawCabalProjectContext for use by load-cabal-plan
- load-cabal-plan: use rawCabalProjectContext concatenation instead of
  appendContext

Add unit tests verifying context flows through parseBlockLines and
parseSourceRepositoryPackages.

* Bump head.hackage

- Simplify protocol_version from [major, minor] to just major
- Minor provides no value for compatibility checks
- Reduces header size by ~1-2 bytes
- Update abstract, specification, era transition sections
- Add rationale for minor removal