[Enh]: Omit `Vector` from results

[JerryNixon]

What?

Vector-type columns are omitted from results by default.

Behavior

• Equivalent to using the exclude permission property, but applied globally.
• Applies only to mssql data sources (for now).

Why?

Vector columns can be large and are rarely read directly. Omitting them by default improves performance and reduces payload size, while still allowing explicit opt-in.

How?

• [ ] Add include-vector-fields-by-default property to configuration.
• [ ] Update JSON schema (true valid only when database-type is mssql).
• [ ] Update dab validate (true valid only when database-type is mssql).
• [ ] Add dab configure --data-source.include-vector-fields-by-default to CLI.
• [ ] REST: Omit vector fields by default; include when explicitly selected.
• [ ] GraphQL: Omit vector fields by default; include when explicitly requested.
• [ ] MCP: Omit vector fields by default; include when explicitly requested.

Configuration

{
  "data-source": {
    "include-vector-fields-by-default": false // default
  }
}

Command Line

dab configure --data-source.include-vector-fields-by-default false
dab configure --data-source.include-vector-fields-by-default true