Gloas: fix test failures (KZG verifier wiring, harness columns, WSS sync)

Brings the FORK_NAME=gloas beacon_chain test suite from 31 failures to green:

- v1 KZG batch verifier couldn't verify Gloas columns. Added
  verify_columns_against_block helper that picks commitments per fork
  (Fulu: inline on column; Gloas: signed_execution_payload_bid).
- BeaconChainHarness::process_envelope didn't persist columns. Now mirrors
  what production does in import_available_execution_payload_envelope.
- get_or_reconstruct_blobs returned an error for Gloas. Now short-circuits to
  Ok(None); WSS test copies columns from source to dest directly.
- update_data_column_signed_header (block_verification tests) only handled
  Fulu shape. Added a Gloas branch that re-keys to canonical_root.
- BlockError::EnvelopeBlockRootUnknown changed to tuple variant.
- Removed duplicate process_payload_envelope_availability.

beacon_node/beacon_chain/src/block_verification.rs

@@ -287,7 +287,7 @@ pub enum BlockError {
     /// https://github.com/sigp/lighthouse/issues/4546
     AvailabilityCheck(AvailabilityCheckError),
     /// The payload envelope's block root is unknown.
-    EnvelopeBlockRootUnknown { block_root: Hash256 },
+    EnvelopeBlockRootUnknown(Hash256),
     /// Optimistic sync is not supported for Gloas payload envelopes.
     OptimisticSyncNotSupported { block_root: Hash256 },
     /// A Blob with a slot after PeerDAS is received and is not required to be imported.