feat(emails): add re-send for all emails, failed tab, and resend indicators

- Add resend_attempts and last_resent_at to email_logs schema and migrations
- Add POST /api/emails/logs/:id/resend and emailService.resendFromLog
- Add resendLog API and EmailLog.resendAttempts/lastResentAt
- Add All/Failed sub-tabs, resend button for all emails, re-sent indicator in logs and detail modal

Made-with: Cursor

backend/src/lib/email.ts

@@ -1342,6 +1342,61 @@ export const emailService = {
       error: result.error 
     };
   },
+
+  /**
+   * Resend an email from an existing log entry
+   */
+  async resendFromLog(logId: string): Promise<{ success: boolean; error?: string }> {
+    const log = await dbGet<any>(
+      (db as any).select().from(emailLogs).where(eq((emailLogs as any).id, logId))
+    );
+
+    if (!log) {
+      return { success: false, error: 'Email log not found' };
+    }
+
+    if (!log.bodyHtml || !log.subject || !log.recipientEmail) {
+      return { success: false, error: 'Email log missing required data to resend' };
+    }
+
+    const result = await sendEmail({
+      to: log.recipientEmail,
+      subject: log.subject,
+      html: log.bodyHtml,
+      text: undefined,
+    });
+
+    const now = getNow();
+    const currentResendAttempts = (log.resendAttempts ?? 0) + 1;
+
+    if (result.success) {
+      await (db as any)
+        .update(emailLogs)
+        .set({
+          status: 'sent',
+          sentAt: now,
+          errorMessage: null,
+          resendAttempts: currentResendAttempts,
+          lastResentAt: now,
+        })
+        .where(eq((emailLogs as any).id, logId));
+    } else {
+      await (db as any)
+        .update(emailLogs)
+        .set({
+          status: 'failed',
+          errorMessage: result.error,
+          resendAttempts: currentResendAttempts,
+          lastResentAt: now,
+        })
+        .where(eq((emailLogs as any).id, logId));
+    }
+
+    return {
+      success: result.success,
+      error: result.error,
+    };
+  },
 };
 
 // Export the main sendEmail function for direct use