add ledger conformance test tarball

Author: rrruko

src/ledger/conformance-test-vectors/README.md

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+vectors.tar.gz is a set of test vectors dumped from the cardano-ledger
+conway-era test suite that can be used to test alternative ledger
+implementations. Each vector consists of one transaction and a pair of "before"
+and "after" ledger states. Vectors are grouped into directories based on the
+unit test that generated the vector, and numbered sequentially.
+
+Test vectors were obtained by running [this](https://github.com/SundaeSwap-finance/cardano-ledger-conformance-tests/commit/34365e427e6507442fd8079ddece9f4a565bf1b9) fork of cardano-ledger.
+
+Ledger V9 tests were removed, as well as two tests (BodyRefScriptsSizeTooBig,
+TxRefScriptsSizeTooBig) that produced very large sequences of transactions
+without a correspondingly significant impact on coverage.
+
+To optimize the size of the vector set, the ledger state format is modified to
+represent protocol parameters records by their hash. Each unique protocol parameters record can be found in the pparams-by-hash directory.
+
+See also:
+[this](https://github.com/IntersectMBO/cardano-ledger/issues/4892#issuecomment-2880444621)
+discussion in the cardano-ledger repository.