Cardano Updates

Wrap `Channel m a` recv values in a new `Reception a = MkReception
!(IntMap Time) !a`, recording per-chunk arrival times.  In the mux
demuxer the chunk's arrival time is paired with its starting byte
offset; codec/driver layers either strip the time map (the codec sees
only bytes) or propagate it through `wrapMiniProtocolTrailing` at the
mini-protocol callback boundary.  Tests/demos/benches use `IntMap.empty`
when synthesising trailing.

This is the network half of the November Leios demo's arrival-time
plumbing; consumers (e.g. Praos block-arrival tracing on the consensus
side) will be wired up separately.

Co-Authored-By: Claude Opus 4.7 <[email protected]>

Upstream cleanup, not Leios-specific: eight unused-import warnings that
upstream's own ghc-options promote to errors via 'nix/ouroboros-network.nix'
('-Werror' on forAllProjectPackages). They've been present at the
'main-peras-5202-merged' SHA that cardano-node and ouroboros-consensus
master both consume; surface when downstream haskell.nix builds also
inherit `-Werror`.

Affected files (one unused qualified import each):
- framework/lib/Ouroboros/Network/Protocol/Handshake/Codec.hs (BL)
- framework/tests-lib/.../ConnectionManager/Experiments.hs (LBS)
- framework/io-tests/.../Driver.hs (List)
- framework/io-tests/.../Socket.hs (IntMap)
- tests/lib/.../TxSubmission/AppV1.hs (BSL)
- tests/lib/.../TxSubmission/AppV2.hs (BSL)
- protocols/tests-lib/.../KeepAlive/Test.hs (BL)
- protocols/tests-lib/.../PeerSharing/Test.hs (BL)

Verified with 'cabal clean && cabal build all --ghc-options=-Werror' →
exit 0.

Co-Authored-By: Claude Opus 4.7 <[email protected]>

Introduce 'Maybe LeiosCert' (mirrored after the existing 'Maybe
PerasCert') as an optional field on the Dijkstra-era 'BlockBody'. Other
eras are unaffected — this is the entire Leios-related ledger changes
from leios-prototype at the time of the remake.

it across eras

across eras

since this is now part of the `StAnnTx` signal

Introduce 'Maybe LeiosCert' (mirrored after the existing 'Maybe
PerasCert') as an optional field on the Dijkstra-era 'BlockBody'. Other
eras are unaffected — this is the entire Leios-related ledger changes
from leios-prototype at the time of the remake.

Add TICK and NEWEPOCH benchmarks

Convert `BLS12381` haddock examples into `doctest`

It doesn't run any tests, this is similar to `cabal build all`.