fix: Translate MFA error messages and placeholders

[sricharan-varanasi]

• Tests for the changes have been added (existing tests pass)
• Related documentation has been added / updated
• OSS packages added to Curious open source credit page
• Delivered the fix or feature branches into develop or release branches via Squash and Merge (to keep clean history)

📝 Description

🔗 Jira Ticket M2-10397
🔗 Jira Ticket M2-10399
🔗 Jira Ticket M2-10400

Fixed MFA flows (setup, disable, and view recovery codes) to properly display French translations for placeholder text and error messages when the application language is changed to French.

Changes include:

• MFAVerificationForm: Added translation wrapper to error display using t(error, { defaultValue: error })
• Error Constants: Converted all hardcoded English error messages to translation keys:
  • MFASetup.const.ts: Updated error messages to use keys like invalidMFACode, mfaSessionExpired, networkError
  • RemoveMFA.constants.ts: Updated error messages to use keys like invalidRecoveryCode, recoveryCodeAlreadyUsed, tooManyAttempts
  • ViewRecoveryCodes.utils.ts: Updated error messages to use translation keys
• Translation Files: Added new mfaAlreadyEnabled translation key in both app-en.json and app-fr.json
• ViewRecoveryCodes Hook: Fixed two hardcoded "Session expired. Please try again." messages to use mfaSessionExpired translation key
• Identity Confirmation Components: Ensured ConfirmIdentityVerificationCode and ConfirmIdentityRecoveryCode properly translate errors

🪤 Peer Testing

1. Log in to the application

2. Navigate to Account Settings → MFA section

3. Change language to French using the language selector

4. Enable MFA and enter an incorrect verification code

   Expected outcome: Error message should appear in French: "Code de vérification invalide"

5. Try to view recovery codes with an incorrect code

   Expected outcome: Error message should appear in French: "Code invalide"

6. Try to disable MFA with an incorrect recovery code

   Expected outcome: Error message should appear in French: "Code de récupération invalide"

7. Wait for session to expire during any MFA flow

   Expected outcome: Error message should appear in French: "Votre session a expiré. Veuillez vous reconnecter."

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[divbzero]

Small copy-paste error. Otherwise looks good!