binding-tier-1: Haskell binding standup (replicate from Chapel pilot)

[hyperpolymath]

Parent: #129.

Scope

Apply the detachable-harness template from
docs/adr/0001-binding-ci-template.adoc to bindings/haskell/.

Detachability contract for the Haskell binding

• bindings/haskell/ — src/, test/, proven.cabal (and/or
  stack.yaml), Justfile, symbol-manifest.txt
• bindings/c/include/proven.h — vendored on extraction; consumed via
  include-dirs: in the cabal file driven by PROVEN_INCLUDE_PATH
• .github/workflows/haskell-ci.yml — workflow + sparse-checkout

Root Justfile gains haskell-{check,build,test,clean} one-line
forwarders. The Haskell binding uses foreign import ccall with
extra-libraries: proven / extra-lib-dirs: driven by
PROVEN_LIB_PATH, not by hardcoded layout.

Replication

• chapel → haskell
• *.chpl → *.hs / *.hsc
• Mason.toml → proven.cabal
• chpl --version → ghc --version / cabal --version
• Chapel chpl --library → cabal build --enable-tests

WIRED subset starts at the proven#88 quintet. Land in a single PR
titled feat(haskell-binding): stand up detachable CI + tests — binding-tier-1.

References

• Parent: proven: binding-tier-1 detachable-harness template — Chapel pilot + replication #129
• Pilot ADR: docs/adr/0002-chapel-binding-standup.adoc
• Template ADR: docs/adr/0001-binding-ci-template.adoc