Cardano Updates

- Pin contra-tracer to Russoul/contra-tracer@5ad4ac8 which adds
  INLINE contramap and strict second argument / result, on top of
  the existing INLINE runTracerA and strict (***) fixes.

- Revert the heap limit from 1500M back to 900M and instead set
  TASTY_NUM_THREADS=1 on all platforms. The OOM is caused by Tasty
  running all tests concurrently (one thread per CPU via
  setNumCapabilities), stacking their peak residencies. Each
  individual test fits well within 900 MB; the fix is sequential
  execution, not a larger limit.

Efficient common case for setCurrentTime

Efficient common case for setCurrentTime

KnownPeers.setCurrentTime and EstablishedPeers.setCurrentTime run on
every governor loop iteration. Add a fast path to KnownPeers for the
common case where nothing is scheduled or the earliest scheduled time
is still in the future; previously it always ran the general path,
rebuilding the record and (with +asserts) checking the invariant.

In EstablishedPeers use findMin instead of minView in the existing
fast-path guard: an O(1) peek that avoids allocating the deletion of
the minimum. The fast path now also covers the empty-queue case, which
previously fell through to the general path.

We only need Eq.

Bumps the pinned tag to include the runTracerA INLINE fix.

Without INLINE, every traceWith call with a nullTracer (Squelching
constructor) allocates a fresh Kleisli wrapper via arr (const ()).  In
the network-mux bearer hot path this amounts to 5 such calls per SDU.
With messages chunked into 1260-byte SDUs, a single 3 MB payload
generates thousands of SDUs and therefore thousands of spurious Kleisli
allocations per traceWith call, producing hundreds of MB of short-lived
GC pressure that pushes the test suite past the 900 MB Hydra limit.

With INLINE on runTracerA and the existing INLINE on traceWith, GHC
reduces traceWith nullTracer x to pure () at the call site: zero
allocation, no GC overhead.