feat: add account toggle, message dedup tracking, SMTP per-user and Gmail OAuth flow plan

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>
Agent-Logs-Url: https://github.com/christianlouis/pop_puller_to_gmail/sessions/b77800ca-b452-4427-b0bf-63403e906916

frontend/src/lib/api.ts

@@ -204,6 +204,11 @@ export const mailAccountsApi = {
     return response.data;
   },
 
+  async toggle(id: number): Promise<MailAccount> {
+    const response = await api.patch<MailAccount>(`/mail-accounts/${id}/toggle`);
+    return response.data;
+  },
+
   async delete(id: number): Promise<void> {
     await api.delete(`/mail-accounts/${id}`);
   },