fix blockchain.transaction.get verbose parameter declared required

[eynhaender]

verbose in blockchain.transaction.get was declared as required instead of optional, causing a "missing parameter" error for protocol v1.2+ clients that omit it per spec.

[eynhaender]

Output of bs if not set correctly while opening a wallet in sparrow:

2026-05-11T13:59:04Z.0 Rpc request : (147) bytes [127.0.0.1:54546] blockchain.scripthash.subscribe(...).
2026-05-11T13:59:04Z.0 Rpc response:  (40) bytes [127.0.0.1:54546] 
2026-05-11T13:59:04Z.0 Rpc request : (147) bytes [127.0.0.1:54546] blockchain.scripthash.subscribe(...).
2026-05-11T13:59:04Z.0 Rpc response:  (40) bytes [127.0.0.1:54546] 
2026-05-11T13:59:04Z.0 Rpc request : (149) bytes [127.0.0.1:54546] blockchain.scripthash.get_history(...).
2026-05-11T13:59:04Z.0 Rpc response:  (132) bytes [127.0.0.1:54546] 
2026-05-11T13:59:04Z.0 Rpc request : (142) bytes [127.0.0.1:54546] blockchain.transaction.get(...).
2026-05-11T13:59:04Z.2 Inbound electrum channel stop [127.0.0.1:54546] missing parameter

Trace output of sparrow wallet

2026-05-11 16:05:04,337 TRACE Sending to electrum server at localhost: {"jsonrpc":"2.0","method":"blockchain.scripthash.subscribe","params":["80b9b98377baff68c485f0efbc4999049b16241190e9780ed191422e19f6ce7a"],"id":34}
2026-05-11 16:05:04,378 TRACE Sending to electrum server at localhost: {"jsonrpc":"2.0","method":"blockchain.scripthash.subscribe","params":["8d92a0654444666b00fcca02673133c432df4e6581c2b5a9b8ca023d9801c0fe"],"id":35}
2026-05-11 16:05:04,420 TRACE Sending to electrum server at localhost: {"jsonrpc":"2.0","method":"blockchain.scripthash.get_history","params":["a13db42725c4fe96e85b54caa985698133eaf07bf90fd391203b53960c50af2e"],"id":36}
2026-05-11 16:05:04,463 TRACE Sending to electrum server at localhost: {"jsonrpc":"2.0","method":"blockchain.transaction.get","params":["263dcf9e5ba26c71f70584e6888426ea97ce41461a9e281656b68b9790eef62a"],"id":37}
2026-05-11 16:05:04,463 TRACE Connection error while reading
2026-05-11 16:05:05,525 TRACE Sending to electrum server at localhost: {"jsonrpc":"2.0","method":"blockchain.transaction.get","params":["263dcf9e5ba26c71f70584e6888426ea97ce41461a9e281656b68b9790eef62a"],"id":38}
2026-05-11 16:05:06,492 TRACE Sending to electrum server at localhost: {"jsonrpc":"2.0","method":"blockchain.transaction.get","params":["263dcf9e5ba26c71f70584e6888426ea97ce41461a9e281656b68b9790eef62a"],"id":39}