Fix write query failing when a named parameter is called :sql

[viraatdas]

Fixes #2761.

When you run a write query containing a named parameter called :sql (for example update docs set title = :sql where id = :id), the generated parameter input on the execute-write form is named sql, which collides with the form's own sql field holding the query text. The user's :sql value then overrides the query for the rest of the form, so the write does not work.

This namespaces the generated parameter form inputs with a _sql_param_ prefix (via a new sql_parameter_name_prefix), so a :sql (or :id, etc.) parameter input no longer collides with the control sql field. The label still shows the bare parameter name, and the JS parameter controls track the original name via data-parameter-name; the execute-write view reads the prefixed fields.

Added an end-to-end regression test (test_execute_write_form_parameter_called_sql) that runs a write query with a :sql parameter and asserts the affected row is updated correctly. It fails before this change.

Prepared with AI assistance.