PreEncodedBlockCert was msgp:ignore'd and encoded with protocol.EncodeReflect, so the block service and the ws fetcher both built block responses through reflection. Switch its codec.Raw fields to msgp.Raw and generate the codec.

The _struct codec:"" tag keeps both fields unconditional, matching EncodedBlockCert, which is what the fetching side decodes these bytes into. Verified byte-identical to the previous reflection encoding over randomized block and certificate pairs, including the empty-field case.

Note that go-codec does not treat msgp.Raw as verbatim msgpack, so every encoder of this type has to move together; protocol.EncodingTest skips randomized comparison for msgp.Raw for the same reason.

TxService encoded its response with protocol.EncodeReflect while the client side already decodes through the generated txSyncResponse decoder. Encode through the same named type so both ends go through msgp, and have getFilteredTxns return it directly.

The wire format is unchanged: TestRandomizedEncodingtxSyncResponse already requires EncodeMsgp and EncodeReflect to agree byte for byte, and the empty response the serve side actually sends is now pinned in the test.

Reject duplicate transaction IDs in checkTxnGroupID and check every group
before evalTxValidator consults the verified transaction cache. The cache
is keyed by transaction ID, so group commitments and distinct IDs must be
validated before lookup. Duplicate detection reuses the existing hashes.

Remove screens covered by WellFormed and the overly strict ban on
heartbeats in resource groups. Verify now calls CheckTxnGroupID directly;
the proposal filter retains state-proof screening.

Security guide

docs(x402): align skill files with @x402/* 2.25 and x402-avm 2.0.2 APIs

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