Fix TypeScript errors blocking Docker build

- Fix Authentik button type casting issue in login page
  * Use exported signIn instead of authClient type assertion
  * Add proper error handling for OAuth calls

- Fix image MIME type handling in import-photo.ts
  * Convert base64 to data URL format for AI SDK compatibility

- Fix type annotations in auth/server.ts changeEmail handler
  * Add explicit type annotation for destructured parameters

These TypeScript errors were preventing 'pnpm build' from completing
during Docker image build process.

apps/web/lib/auth/server.ts

@@ -128,7 +128,7 @@ export const auth = betterAuth({
     },
     changeEmail: {
       enabled: true,
-      sendChangeEmailVerification: async ({ newEmail, url }) => {
+      sendChangeEmailVerification: async ({ newEmail, url }: { newEmail: string; url: string }) => {
         await sendEmail({
           to: newEmail,
           subject: "Verify your new Epicure email",