`eth_subscribe` returns wrong data structure for `newHeads`

[LesnyRumcajs]

Describe the bug

In the eth_subscribe method, with newHeads, Forest returns incorrect data structure. This causes errors with tooling such as Filecoin Subway (see the issue where it was discovered #6334)

Forest:

❯ websocat ws://127.0.0.1:2345/rpc/v1
{"jsonrpc":"2.0","id":1,"method":"eth_subscribe","params":["newHeads"]}
{"jsonrpc":"2.0","id":1,"result":"0xaa047d05aff3e4d6b65aace000dfb863eca9b077c5bc78920bdd799a8b267493"}
{"jsonrpc":"2.0","method":"eth_subscription","params":{"subscription":"0xaa047d05aff3e4d6b65aace000dfb863eca9b077c5bc78920bdd799a8b267493","result":[{"Miner":"t04040","Ticket":{"VRFProof":"iBD1MNFZT1fKuYRDSmEQSPwKyFc/img4cmpBp+5Goud0VbGS+GnBl66K6gTv0rAxGZSd0Ly+tmq1Zv84FVHxfbfQyG7FYE80j02s+fovB/5Et2nOJ8+FBC9PgxMA18vh"},"ElectionProof":{"VRFProof":"ozXtp0IjCy+uYTZ5OizGPM2p9D7YwCIXXgk2Sy91/h6UCY4tJpd/CMlvH4jArClCElxATXR2I/ssUh+j/+hHOO8sOORZOaqEYunDIS4z+1/bZkU4mI0ST1IWhLf9BOaQ","WinCount":1},"BeaconEntries":[{"Round":25032922,"Data":"jNi9LJydzD85VZIDzCTI90enSresdS4GE6IOPM09DRF/J7Dbfrjf35WcQ7ISyVoJ"}],"WinPoStProof":[{"PoStProof":3,"ProofBytes":"szbeAwE7BxktEkUJ/mNYLmDRcD+5cO+mCx75IOo5h8H9LNCnYCa0W+9NPwGuKTOwpj2t8iOpYs3IEPKW/Bc9ONa5aXpAFx51jd/R54FDB+SFAUpdlacIguCPE2d7ul9sAIBh22ctMxHmGvo2P4tnJ65j7EiMQg54E/RazReFOJxmcTEAxSKZERcaybaR1alip6YYxTNc5lapw6kDp8j89Y27jggOiFy20pCc7GR42dzjE1Y4ehW17KfgmiBm2EER"}],"Parents":[{"/":"bafy2bzaceawvt5luhe674uc3e4tg5wimyb3mvz4vct4xir53ut4fvuupymk76"},{"/":"bafy2bzaceb6aiqbiy7qnf4ltscqm3libty2mvjbhale6uknnn6wn622ezvljo"}],"ParentWeight":"62453403183","Height":3352526,"ParentStateRoot":{"/":"bafy2bzacec6yv7bvzawxmtyc47seghtahcnaycenvgtqczjbswlftanl6un4o"},"ParentMessageReceipts":{"/":"bafy2bzacebqlpgjjstdytmpddnojlae3qycozkg3ifhcwty5scewgjlrdhisc"},"Messages":{"/":"bafy2bzacecjl4q7lt3lt2rkywf5ldtcnz4mkcjvkr74wvquf3hnnkbu66pazc"},"BLSAggregate":{"Type":2,"Data":"wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"},"Timestamp":1767902160,"BlockSig":{"Type":2,"Data":"goroH3YZ6qs+YVvPk6tyVARVHO6OHgd+ZIo7v4SCqn593YtnGh46x+YxK45EHf4FBigUNI8gNa6ARxa14muJX5BGnHnM4ONbvhBLx3cyvAtgIgFmXdyIrP+KJx5zTcyG"},"ForkSignaling":0,"ParentBaseFee":"115"}

Forest returns TipsetHeader, i.e.,

forest/src/blocks/header.rs

Lines 228 to 236 in 78af57e

	/// A [`RawBlockHeader`] which caches calls to [`RawBlockHeader::cid`] and [`RawBlockHeader::verify_signature_against`]
	#[cfg_attr(test, derive(Default))]
	#[derive(Debug, GetSize)]
	pub struct CachingBlockHeader {
	uncached: RawBlockHeader,
	#[get_size(ignore)]
	cid: OnceLock<Cid>,
	has_ever_been_verified_against_any_signature: AtomicBool,
	}

Lotus:

{"id":1,"jsonrpc":"2.0","result":"0x9e0226a732eb48ac8161a8b3b55a0e4000000000000000000000000000000000"}
{"jsonrpc":"2.0","method":"eth_subscription","params":{"subscription":"0x9e0226a732eb48ac8161a8b3b55a0e4000000000000000000000000000000000","result":{"hash":"0x67b57ede46007adf08be9c78281049b9086b2f61727dc889127d3993dd98c9ec","parentHash":"0x29cc3b7e3fd5b9dd82a27b9e008255b859c747663b98c2eca63b2ba8cf7d5caa","sha3Uncles":"0x1dcc4de8dec75d7aab85b567b6ccd41ad312451b948a7413f0a142fd40d49347","miner":"0x0000000000000000000000000000000000000000","stateRoot":"0x0000000000000000000000000000000000000000000000000000000000000000","transactionsRoot":"0x0000000000000000000000000000000000000000000000000000000000000000","receiptsRoot":"0x0000000000000000000000000000000000000000000000000000000000000000","logsBloom":"0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff","difficulty":"0x0","totalDifficulty":"0x0","number":"0x333021","gasLimit":"0x4a817c800","gasUsed":"0xfdf421b6","timestamp":"0x6961058a","extraData":"0x","mixHash":"0x0000000000000000000000000000000000000000000000000000000000000000","nonce":"0x0000000000000000","baseFeePerGas":"0x66","size":"0x0","transactions":[{"chainId":"0x4cb2f","nonce":"0x1005b0","hash":"0xa7868a9e2255a1e587928ebd28ec9e3a1202816e3eecaefe8165b08a41e59292","blockHash":"0x67b57ede46007adf08be9c78281049b9086b2f61727dc889127d3993dd98c9ec","blockNumber":"0x333021","transactionIndex":"0x0","from":"0x0f96b5f075e13c3a552c1481a1ae00f9c042d58b","to":"0x445238eca6c6ab8dff1aa6087d9c05734d22f137","value":"0x0","type":"0x0","input":"0x45c0b92d00000000000000000000000000000000000000000000000000000000000000e3000000000000000000000000000000000000000000000000000000000033302b00000000000000000000000000000000000000000000000000000000000000600000000000000000000000000000000000000000000000000000000000000000","gas":"0xf4500bb","gasPrice":"0x18fcd","accessList":null,"v":"0x99682","r":"0x440740a47f602e52eb049d4befe53bc0464180ebc6da91e4bcff73ef399a18eb","s":"0x74c4e739aaf9ffdbbefb531c5b802989989189a5fd3fc2020af849ff85b8d2cb"},{"chainId":"0x4cb2f","nonce":"0x42acf","hash":"0x29d2817f8594fb9cd49680de8e97c41c61a1929bf837ab889c2271f221eb91e9","blockHash":"0x67b57ede46007adf08be9c78281049b9086b2f61727dc889127d3993dd98c9ec","blockNumber":"0x333021","transactionIndex":"0x1d","from":"0x483f1cd029efcfe5ebe382a8d63e73b0e53c7778","to":"0x85e366cf9dd2c0ae37e963d9556f5f4718d6417c","value":"0x0","type":"0x0","input":"0x45c0b92d00000000000000000000000000000000000000000000000000000000000011a900000000000000000000000000000000000000000000000000000000003330f600000000000000000000000000000000000000000000000000000000000000600000000000000000000000000000000000000000000000000000000000000000","gas":"0xa343064","gasPrice":"0x18d95","accessList":null,"v":"0x99681","r":"0x204b253540e42cc6afcfebb2c35735ac25aa903a91bcdc2a74ab684f760f0a19","s":"0x4a9d6fd313f32bb838a0725c8fc64a6aba22cedfa22490042af9b9a08253e9e1"}],"uncles":[]}},"meta":{"SpanContext":"AAA3yUBq/bXG1egoo5BRIm7HATjyfd5VqcBMAgA="}}

https://github.com/filecoin-project/lotus/blob/c3b13a6baf1ebfe84757a168d9090609909bac25/node/impl/eth/subscriptions.go#L192-L213

which as a EthBlock

To reproduce

See commands in the summary.

Expected behaviour

Forest returns Ethereum-style blocks and not Filecoin tipset headers.

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