fix: correct import paths and remove DatabaseError export

- Fix BaseLayout import paths in auth email templates from
  `../../core/...` to `../../../core/...` to match correct
  directory depth
- Remove unused `DatabaseError` from db.js exports

src/core/database/db.js

@@ -180,7 +180,6 @@ async function tableExists(tableName) {
 }
 
 export {
-  DatabaseError,
   query,
   queryOne,
   queryAll,

src/features/auth/templates/PasswordChangedEmail.jsx

@@ -1,5 +1,5 @@
 import { Section, Text } from "@react-email/components";
-import { BaseLayout } from "../../core/email/templates/BaseLayout.jsx";
+import { BaseLayout } from "../../../core/email/templates/BaseLayout.jsx";
 
 export const PasswordChangedEmail = ({ email, companyName }) => (
   <BaseLayout

src/features/auth/templates/PasswordResetEmail.jsx

@@ -1,5 +1,5 @@
 import { Button, Section, Text, Link } from "@react-email/components";
-import { BaseLayout } from "../../core/email/templates/BaseLayout.jsx";
+import { BaseLayout } from "../../../core/email/templates/BaseLayout.jsx";
 
 export const PasswordResetEmail = ({ resetUrl, companyName }) => (
   <BaseLayout

src/features/auth/templates/VerificationEmail.jsx

@@ -1,5 +1,5 @@
 import { Button, Section, Text, Link } from "@react-email/components";
-import { BaseLayout } from "../../core/email/templates/BaseLayout.jsx";
+import { BaseLayout } from "../../../core/email/templates/BaseLayout.jsx";
 
 export const VerificationEmail = ({ verificationUrl, companyName }) => (
   <BaseLayout