fix(connectors): throw on misconfigured typeform/zendesk sources instead of returning null

A null from getDocument reads as documented absence, so on an add the
document is dropped with neither a failure counter nor a log. Both
listDocuments paths already throw on the same missing config.

Author: waleedlatif1

apps/sim/connectors/typeform/typeform.ts

@@ -481,7 +481,13 @@ export const typeformConnector: ConnectorConfig = {
     syncContext?: Record<string, unknown>
   ): Promise<ExternalDocument | null> => {
     const formId = (sourceConfig.formId as string)?.trim()
-    if (!formId || !externalId) return null
+    /**
+     * A misconfigured source is a failure, not an absent response. Returning
+     * `null` reads as documented absence, which on an `add` drops the document
+     * with no counter and no log. `listDocuments` throws on the same condition.
+     */
+    if (!formId) throw new Error('Form ID is required')
+    if (!externalId) throw new Error('Response ID is required')
 
     const form = await getFormDefinition(accessToken, formId, syncContext)
     const fieldTitles = buildFieldTitleMap(form)

apps/sim/connectors/zendesk/zendesk.ts

@@ -532,7 +532,12 @@ export const zendeskConnector: ConnectorConfig = {
     externalId: string
   ): Promise<ExternalDocument | null> => {
     const subdomain = (sourceConfig.subdomain as string)?.trim()
-    if (!subdomain) return null
+    /**
+     * A misconfigured source is a failure, not an absent document. Returning
+     * `null` reads as documented absence, which on an `add` drops the document
+     * with no counter and no log. `listDocuments` throws on the same condition.
+     */
+    if (!subdomain) throw new Error('Subdomain is required')
 
     try {
       const baseUrl = buildBaseUrl(subdomain)