Merge #7610: test: wait for MN disconnect after in-place ProUpServ migration

107171b test: wait for MN disconnect after in-place ProUpServ migration (pasta)

Pull request description:

  ## Issue being fixed or feature implemented
  - `feature_protx_version.py` flakes on the ASAN job because a post-v24 in-place `update_service` migration re-encodes `pubKeyOperator`. CMNAuth then drops verified connections, and the default `generate()` → `sync_all()` path asserts that every node still has at least one peer.
  - Same race this test already handles for revoke and registrar key rotation; this path was missing `sync_fun=self.no_op`.

  ## What was done?
  - Mine the ProUpServTx with `sync_fun=self.no_op`.
  - Wait for the migrated masternode's old peers to disconnect, reconnect it to node 0, then `sync_all()`.
  - Keep the `protx` / `getrawtransaction` checks on the mining node, which already has the block.

  ## How Has This Been Tested?
  - Compared against the existing revoke and `update_registrar` disconnect handling in the same file.
  - Root-caused from https://github.com/PastaPastaPasta/dash/actions/runs/31740186678/job/94598843934 (`feature_protx_version.py` failed 3/3 on `sync_blocks` peer-count assert; no AddressSanitizer report).
  - Did not re-run the full functional test locally; it is a long masternode test and the failure is a timing race that shows up under ASAN slowdown.

  ## Breaking Changes
  - None.

  ## Checklist:
  - [x] I have performed a self-review of my own code
  - [x] I have commented my code, particularly in hard-to-understand areas
  - [x] I have added or updated relevant unit/integration/functional/e2e tests
  - [ ] I have made corresponding changes to the documentation
  - [ ] I have assigned this pull request to a milestone _(for repository code-owners and collaborators only)_

  This pull request was created by Codex.

ACKs for top commit:
  knst:
    ACK 107171b

Tree-SHA512: e019c170d94f0d6e2b477da2c9dfe84beeba64529f07cb1fade85ce94b80c5d571ffeb9217c6e570da21c02c6b8b975fca4b655fdd25d2b01ee232dc86fff0f4

Author: PastaPastaPasta

test/functional/feature_protx_version.py

@@ -258,18 +258,19 @@ def test_protx_v24_versioning(self, mn: MasternodeInfo, legacy_mn: MasternodeInf
         upserv_hash = surviving_legacy_mn.update_service(node, submit=True,
                                                          addrs_core_p2p=[f'127.0.0.1:{surviving_legacy_mn.nodePort}'])
         self.bump_mocktime(10 * 60 + 1)
-        tip = self.generate(node, 1)[0]
+        # Same CMNAuth disconnect as a key rotation: SetStateVersion re-encodes pubKeyOperator, so
+        # skip sync_all until the old peers are gone and this node is reconnected.
+        assert surviving_legacy_mn.nodeIdx is not None
+        old_peer_ids = self.get_peer_ids(surviving_legacy_mn.nodeIdx)
+        tip = self.generate(node, 1, sync_fun=self.no_op)[0]
         assert_equal(node.getrawtransaction(upserv_hash, 1, tip)['proUpServTx']['version'], 3)
         state = node.protx('info', surviving_legacy_mn.proTxHash)['state']
         assert_equal(state['version'], 3)  # migrated in place
         # Same operator key, re-encoded to the basic scheme (different hex, but not a rotation: the
         # masternode is not PoSe-banned).
         assert state['pubKeyOperator'] != key_before
         assert_equal(state['PoSeBanHeight'], -1)
-        # The key re-encoding churns the migrated node's masternode connections, so reconnect it (as
-        # the rotation path does) before syncing, then confirm the list still reloads from disk
-        # identically after the in-place migration.
-        assert surviving_legacy_mn.nodeIdx is not None
+        self.wait_for_peers_disconnected(surviving_legacy_mn.nodeIdx, old_peer_ids)
         self.connect_nodes(surviving_legacy_mn.nodeIdx, 0)
         self.sync_all()
         list_before = self.nodes[1].masternodelist()