refactor: remove low-level email retry

Spending too much time on retries in the low level email sending clogs the email-queue-step.
This can lead to cascading delays if there is an outage with our sender provider.
This will cause a vercel runtime failure.
Removing the retry logic also obviates the need for separate funcs.

Author: nams1570

apps/backend/src/lib/emails-low-level.tsx

@@ -203,7 +203,23 @@ export async function lowLevelSendEmailDirectWithoutRetries(options: LowLevelSen
   canRetry: boolean,
   message?: string,
 }>> {
-  return await _lowLevelSendEmailWithoutRetries(options);
+  if (!options.to) {
+    throw new StackAssertionError("No recipient email address provided to sendEmail", omit(options, ['emailConfig']));
+  }
+
+  const result = await _lowLevelSendEmailWithoutRetries(options);
+
+  if (result.status === 'error') {
+    console.warn("Failed to send email.", {
+      host: options.emailConfig.host,
+      from: options.emailConfig.senderEmail,
+      to: options.to,
+      subject: options.subject,
+      error: result.error,
+    }, result.error.rawError);
+  }
+
+  return result;
 }
 
 // currently unused, although in the future we may want to use this to minimize the number of requests to Resend
@@ -244,62 +260,3 @@ export async function lowLevelSendEmailResendBatchedDirect(resendApiKey: string,
   return result;
 }
 
-export async function lowLevelSendEmailDirectViaProvider(options: LowLevelSendEmailOptions): Promise<Result<undefined, {
-  rawError: any,
-  errorType: string,
-  canRetry: boolean,
-  message?: string,
-}>> {
-  if (!options.to) {
-    throw new StackAssertionError("No recipient email address provided to sendEmail", omit(options, ['emailConfig']));
-  }
-
-  class DoNotRetryError extends Error {
-    constructor(public readonly errorObj: {
-      rawError: any,
-      errorType: string,
-      canRetry: boolean,
-      message?: string,
-    }) {
-      super("This error should never be caught anywhere else but inside the lowLevelSendEmailDirectViaProvider function, something went wrong if you see this!");
-    }
-  }
-
-  let result;
-  try {
-    result = await Result.retry(async (attempt) => {
-      const result = await lowLevelSendEmailDirectWithoutRetries(options);
-
-      if (result.status === 'error') {
-        const extraData = {
-          host: options.emailConfig.host,
-          from: options.emailConfig.senderEmail,
-          to: options.to,
-          subject: options.subject,
-          error: result.error,
-        };
-
-        if (result.error.canRetry) {
-          console.warn("Failed to send email, but error is possibly transient so retrying.", extraData, result.error.rawError);
-          return Result.error(result.error);
-        }
-
-        console.warn("Failed to send email, and error is not transient, so not retrying.", extraData, result.error.rawError);
-        throw new DoNotRetryError(result.error);
-      }
-
-      return result;
-    }, 3, { exponentialDelayBase: 2000 });
-  } catch (error) {
-    if (error instanceof DoNotRetryError) {
-      return Result.error(error.errorObj);
-    }
-    throw error;
-  }
-
-  if (result.status === 'error') {
-    console.warn("Failed to send email after all retries!", result.error);
-    return Result.error(result.error.errors[0]);
-  }
-  return Result.ok(undefined);
-}