Cardano Updates

  Light wallets (Eternl, Lace, Yoroi) export HD-derived extended keys
  (PaymentExtendedKey — BIP32-Ed25519) which Hydra previously rejected.
  Convert extended keys to normal PaymentKey at load time so users can
  use wallet-exported key files directly with --cardano-signing-key and
  --cardano-verification-key without manual conversion.

checkPartialFanout now verifies that headInValue equals headOutValue plus the sum of all distributed output values, preventing Ada theft via outputs not counted by the membership proof. The off-chain partialFanoutTx builder is updated accordingly to subtract distributed values from the continuing head output.

Tighten the GHCi-based schema generator so generated message schemas line
up more closely with the current tracer implementations.

This changes the generator in a few important ways:
- add a `--prune-stale-properties` mode to drop schema properties that are
  no longer supported by current inference
- preserve surviving schemas while still allowing inferred fields to be
  added or upgraded
- emit `required` fields for inferred non-optional payload keys
- improve namespace parsing for multiline `namespaceFor` clauses and
  `namespaceFor = \case` definitions
- improve `forMachine` parsing for multiline headers, nested expressions,
  lambda-case bodies, helper-emitted object fragments, and multiple
  `".="` fields on one line
- improve constructor matching and normalize qualified constructor names so
  `forMachine` and `namespaceFor` resolve to the same event
- scope handshake fallback matching to the Diffusion tracer instead of a
  global `AnyMessageAndAgency` fallback
- improve RHS inference for rendered strings, integers, booleans, arrays,
  objects, and `toJSONList` payloads
- improve GHCi signature parsing so multiline signatures and tuple results
  are handled correctly

Regenerate the message and type schemas with the new generator. This
restores missing payload fields in a number of messages, removes stale
historical fields from others, preserves useful refs in surviving
properties, and generally improves the accuracy of generated trace
schemas.

Also add/update generated trace documentation.