Implement Blockfrost queries based on OpenAPI spec [Metatask]

[errfrom]

This issue lists all the Blockfrost queries that we need to implement, divided into logical blocks so that the work can be done by multiple developers in parallel. Feel free to assign yourself (please put your username next to the task you are working on).

All work should be based on #1260 Make Contract query backend configurable.

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1. Get utxos at address / by output reference (@errfrom #1366)

• utxosAt - https://docs.blockfrost.io/#tag/Cardano-Addresses/paths/~1addresses~1{address}~1utxos/get
• getUtxoByOref - https://docs.blockfrost.io/#tag/Cardano-Transactions/paths/~1txs~1{hash}~1utxos/get

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2. Get transaction metadata, Check transaction confirmation status (@jy14898 #1368)

• getTxMetadata - https://docs.blockfrost.io/#tag/Cardano-Transactions/paths/~1txs~1{hash}~1metadata/get
• isTxConfirmed - https://docs.blockfrost.io/#tag/Cardano-Transactions/paths/~1txs~1{hash}/get

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3. Submit / evaluate a transaction (@jy14898 #1376)

• submitTx - https://docs.blockfrost.io/#tag/Cardano-Transactions/paths/~1tx~1submit/post
• evaluateTx - https://docs.blockfrost.io/#tag/Cardano-Utilities/paths/~1utils~1txs~1evaluate/post

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4. Get datums / scripts by hash (@uhbif19 #1378)

• getDatumByHash - https://docs.blockfrost.io/#tag/Cardano-Scripts/paths/~1scripts~1datum~1{datum_hash}~1cbor/get
• getScriptByHash:
  • get timelock script by hash - https://docs.blockfrost.io/#tag/Cardano-Scripts/paths/~1scripts~1{script_hash}~1json/get
  • get plutus script by hash - https://docs.blockfrost.io/#tag/Cardano-Scripts/paths/~1scripts~1{script_hash}~1cbor/get

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5. Get current epoch information (@Luis-omega #1372)

• getProtocolParameters - https://docs.blockfrost.io/#tag/Cardano-Epochs/paths/~1epochs~1latest~1parameters/get
• getCurrentEpoch - https://docs.blockfrost.io/#tag/Cardano-Epochs/paths/~1epochs~1latest/get

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6. Get blockchain information (@errfrom #1377)

• getSystemStart - https://docs.blockfrost.io/#tag/Cardano-Ledger/paths/~1genesis/get
• getEraSummaries - https://docs.blockfrost.io/#tag/Cardano-Network/paths/~1network~1eras/get
• getChainTip - https://docs.blockfrost.io/#tag/Cardano-Blocks/paths/~1blocks~1latest/get

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[Luis-omega]

I would like to take 5. Get current epoch information