Cardano Updates

## Summary
- Add macOS boot sync workflow (preview + mainnet) on self-hosted runner
(#5129)
- Replace Buildkite references with GitHub Actions in docs (#5137)
- Add GHA migration decision log

## Test plan
- [ ] macOS boot sync jobs (preview + mainnet) run on this PR
- [ ] Remove `pull_request` trigger after successful run

The latency benchmark used ResourceT to write the CSV file during
cleanup, but by that time the cluster teardown via race_ had already
run, causing "permission denied" errors.

Move CSV reporter creation from ResourceT into the outer ContT layer
so the write happens after withShelleyServer returns but before the
ContT continuation exits.

Also use absolute paths ($GITHUB_WORKSPACE) for BENCHMARK_CSV_FILE,
matching what the old Buildkite pipeline did with $(pwd).

Dispatch-only + push-to-master workflow that runs preview and mainnet
boot sync tests on the macOS self-hosted runner.

Badges, CI docs, release checklist, and runner setup now
point to GHA workflows after the CI migration.

The DLLs in the haskell.nix output are symlinks to other store paths.
`cp -R` preserves these symlinks, so `chmod +w` follows them back to
the read-only nix store and fails with "Operation not permitted" on the
CI builder (nix 2.24.11).

Adding `-L` makes cp dereference all symlinks, producing real copies
that can be chmod'd normally.

Fixes #5131

Fixes #5131

Move fourmolu/hlint/stylish-haskell from buildPackages.buildPackages
to pkgs.haskellPackages where the ghc-lib-parser overlay applies.
Add modules patch to HLS shell.tools for the GHC 9.8.2 build.

Remove benchmarks from the Windows testing bundle — JuicyPixels ANN
pragmas crash iserv-proxy during cross-compilation and benchmarks
aren't useful on Windows.

Fix ghc-lib-parser overlay to apply via haskellPackages.override
instead of haskell.packageOverrides which wasn't reaching the
nixpkgs haskell package set used by dev shell tools (fourmolu).

The {-# ANN #-} pragmas in fgl trigger TH evaluation via iserv-proxy
under Wine, which crashes during Windows cross-compilation even with
GHC 9.8.2's win-reloc patch. Strip the HLint ANN lines (no functional
impact) during Windows builds only.

- CheckpointsSpec: drop 1 → pattern match with error (not vacuous True)
- SequentialSpec/SharedSpec: BS.drop 1 → BS.uncons with error
- db-bench: restore error on empty range instead of silent "[]"
- RangeSpec: fromJust (also partial) → explicit pattern match
- TxSeq: restore infinite lists instead of truncating to 1001 elements

The overlay used --replace-fail which breaks when the nixpkgs
ghc-lib-parser (9.6.x) doesn't contain atomic_inc64. Guard the
substitution with a grep check.

haskell.nix's win-reloc-x86_64-pc64.patch is only applied for
GHC < 9.8.3. Without it, iserv-proxy crashes during Windows
cross-compilation when evaluating Template Haskell.

fgl's {-# ANN #-} pragmas trigger Template Haskell evaluation via
iserv-proxy which crashes during Windows cross-compilation.
Strip the HLint annotations (no functional impact) before building.

The ghc-lib-parser 9.8.5.20250214 introduced a regression where
genSym.c calls atomic_inc64 which doesn't exist on the build
platform. This breaks the dev shell (fourmolu, hlint, etc).

Apply the same fix as upstream (digital-asset/ghc-lib#571):
replace atomic_inc64 with atomic_inc.

- Use error with descriptive messages instead of silently changing
  semantics (e.g. returning default values)
- Replace NE.!! with pattern matching in LayerSpec.hs
- Extract minPort/maxPort as top-level definitions to avoid repetition
- Use case pattern matching instead of tail/drop 1 to preserve crash
  semantics on impossible cases

These workflow files still exist on master with pull_request triggers.
Without overriding them in this branch, GitHub Actions runs the master
versions on PRs, causing spurious cancelled/failed checks.