fix(providers): make the tool-call id argument required, not optional

The TSDoc claimed a provider that cannot supply an id would fail to compile, but
the parameter was declared `toolCallId?: string` — so a new call site could omit
it entirely, typecheck, and silently take the unstable-token path the positional
parameter exists to close. The comment promised a guarantee the type did not
enforce.

It is now `string | undefined`: required in position, nullable in value. A
provider with no model-supplied id must pass `undefined` explicitly and take the
loud fallback, rather than being able to forget the argument.

All 27 existing call sites already pass it, so this is enforcement only. Verified
by deleting the argument at one site: `tsc` rejects it.

Author: icecrasher321

apps/sim/providers/utils.ts

@@ -1574,12 +1574,13 @@ export function prepareToolExecution(
   /**
    * The model's own id for this tool call, read from the provider's response.
    *
-   * Passed positionally because every provider already has the tool call in
-   * scope at this point but names it differently, and because a provider that
-   * cannot supply one should fail to compile rather than silently fall through
-   * to the unstable-token path.
+   * Required rather than optional — `string | undefined` — so the argument
+   * cannot be forgotten. A provider with no model-supplied id must pass
+   * `undefined` explicitly and take the loud fallback; omitting it entirely
+   * would silently leave `invocationId` unset, which is the unstable-token path
+   * this parameter exists to close.
    */
-  toolCallId?: string
+  toolCallId: string | undefined
 ): {
   toolParams: Record<string, any>
   executionParams: Record<string, any>