[fix](fe) Fix prepared statement forwarding losing param types on cached execute

[Asthenia0412]

What problem does this PR solve?

Issue Number: close #65848

Problem Summary:

A prepared write statement executed on a non-master FE and forwarded to the master FE fails with NoSuchElementException (errCode 1105) on cached COM_STMT_EXECUTE.

Reproduction:

1. Connect to a non-master FE with a MySQL client supporting prepared statements.
2. PREPARE / EXECUTE an INSERT ... VALUES (?, ...) statement (the first execute sends new_params_bind_flag = 1 with the parameter types).
3. Run the same prepared statement again without re-prepare. The client sends a cached execute with new_params_bind_flag = 0, so the parameter types are omitted from the packet.
4. Because the statement is a write statement, the follower forwards COM_STMT_EXECUTE to the master FE. The master re-prepares the statement and never sees the parameter types, so it cannot decode the parameter values and fails.

Root cause:

In MysqlConnectProcessor.handleExecute, the forwarded COM_STMT_EXECUTE buffer is set before the parameter types are parsed. On a cached repeat execute the client omits the types (new_params_bind_flag == 0), and the forwarded buffer contains only the null bitmap and the parameter values, so the master cannot decode them.

Fix:

When a cached execute omits the parameter types, embed the types known from the first execute into the forwarded buffer and set new_params_bind_flag = 1. The buffer keeps the standard MySQL COM_STMT_EXECUTE layout (null bitmap | flag | parameter types | parameter values), so older masters accept it unchanged. Zero-parameter executes keep forwarding the raw (empty) buffer.

Release note

None

Check List (For Author)

• Test: Unit test MysqlConnectProcessorPreparedStmtForwardTest covering cached execute, first execute and zero-parameter cases.
• Behavior changed: No
• Does this need documentation: No

[Asthenia0412]

cc @wudi @morrySnow PTAL, thanks!

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