bd7f27d refactor: feature_csv_activation.py: move tx helper functions to methods (Sebastian Falbesoner)
2eca46b test: use MiniWallet for feature_csv_activation.py (Sebastian Falbesoner)

Pull request description:

  This PR enables one more of the non-wallet functional tests (feature_csv_activation.py) to be run even with the Bitcoin Core wallet disabled by using the new MiniWallet instead, as proposed in bitcoin#20078.

  Short reviewers guideline:
  - Since we exclusively work with anyone-can-spend outputs here (raw scriptPubKey = OP_TRUE), signing is not needed anymore. The function `sign_transaction` and its calls are removed, after changing a tx (e.g. its scriptSig or nVersion) a simple `.rehash()` call is sufficient. Also, generating an address `self.nodeaddress` (and with that, passing it to the the various test tx creation/sending helper methods) is not needed anymore and removed.
  - The test repeatedly uses the same input for creating different txs (e.g. with different txversions 1 and 2). To let `MiniWallet` create a tx with a specific input, we have to call `.get_utxo()` before which also marks the UTXO as spent. The method is changed to also support keeping the UTXO in its internal list (`mark_as_spent=False`). With the behaviour on master, the second call to `.get_utxo()` with the same input would fail.
  - To keep the diff in the first commit short, the `miniwallet` is set as a global variable, to avoid passing it on every tx creation/spending helper. The global is eliminated in the second (refactoring) commit, where all the helpers are moved to the test class as methods. By that, we can use `self.nodes[0]` directly in the helpers and don't have to pass it again and again. I think there could still be a lot of improvements/refactoring done in the test, but that should hopefully serve as a good basis.

ACKs for top commit:
  laanwj:
    Code review ACK bd7f27d
  MarcoFalke:
    review ACK bd7f27d 🐕

Tree-SHA512: 24fb6a0f7702bae40d5271d197119827067d4b597e954d182e4c1aa5d0fa870368eb3ffed469b26713fa8ff8eb3ecc06abc80b2449cd68156d5559e7ae8a2b11

4bea301 test: use P2PK-MiniWallet for feature_csv_activation.py (Sebastian Falbesoner)
dc7eb64 test: MiniWallet: add P2PK support (Sebastian Falbesoner)

Pull request description:

  This PR adds support for creating and spending transactions with raw pubkey (P2PK) outputs to MiniWallet, [as suggested by MarcoFalke](bitcoin/bitcoin#21900 (comment)). Using that  mode in the test `feature_csv_activation.py`, all txs submitted to the mempool follow the standard policy, i.e. `-acceptnonstdtxn=1` can be removed.

  Possible follow-ups:
  * Improve MiniWallet constructor Interface; an enum-like parameter instead of two booleans would probably be better
  * Look at other tests that could benefit from P2PK (e.g. feature_cltv.py?)
  * Check vsize also for P2PK txs (vsize varies due to signature, i.e. a range has to be asserted)

ACKs for top commit:
  laanwj:
    Code review ACK 4bea301

Tree-SHA512: 9b428e6b7cfde59a8c7955d5096cea88af1384a5f49723f00052e9884d819d952d20a5ab39bb02f9d8b6073769c44462aa265d84a33e33da33c2d21670c488a6

4bea301 test: use P2PK-MiniWallet for feature_csv_activation.py (Sebastian Falbesoner)
dc7eb64 test: MiniWallet: add P2PK support (Sebastian Falbesoner)

Pull request description:

  This PR adds support for creating and spending transactions with raw pubkey (P2PK) outputs to MiniWallet, [as suggested by MarcoFalke](bitcoin#21900 (comment)). Using that  mode in the test `feature_csv_activation.py`, all txs submitted to the mempool follow the standard policy, i.e. `-acceptnonstdtxn=1` can be removed.

  Possible follow-ups:
  * Improve MiniWallet constructor Interface; an enum-like parameter instead of two booleans would probably be better
  * Look at other tests that could benefit from P2PK (e.g. feature_cltv.py?)
  * Check vsize also for P2PK txs (vsize varies due to signature, i.e. a range has to be asserted)

ACKs for top commit:
  laanwj:
    Code review ACK 4bea301

Tree-SHA512: 9b428e6b7cfde59a8c7955d5096cea88af1384a5f49723f00052e9884d819d952d20a5ab39bb02f9d8b6073769c44462aa265d84a33e33da33c2d21670c488a6