docs(thrift): clarify metricViewMetadata false ≡ omit in JSDoc

Address DA review note N4 on PR #397: the public type is `boolean` (not
`true`-literal), but the wiring treats `false` and omitted identically.
Spell that out in the JSDoc so callers don't expect `false` to clear a
server-side default.

Co-authored-by: Isaac
Signed-off-by: Madhavendra Rathore <madhavendra.rathore@databricks.com>

Author: msrathore-db

lib/contracts/IDBSQLSession.ts

@@ -33,6 +33,11 @@ export type ExecuteStatementOptions = {
    * forwarded via the Thrift `confOverlay`. Applies to a single statement only;
    * does not persist across queries.
    *
+   * Setting `false` is equivalent to omitting the option — both leave
+   * `confOverlay` untouched and the server's session default applies. The
+   * option is opt-in only; there is no way to explicitly clear a server
+   * default from the client.
+   *
    * Equivalent SEA wiring will route the same key through napi `statementConf`
    * once the kernel statement-options surface lands — until then this knob is
    * honored only on the Thrift backend.