* feat(mailer): add i18n support for all transactional emails with pt-BR translations
- Create Liquid i18n filter (LiquidFilters::I18nFilter) exposing I18n.t() as `t` filter
with interpolation support via positional args
- Replace hardcoded English strings in all 26 Liquid email templates with i18n keys
- Replace hardcoded English strings in all 5 Devise ERB email templates (OSS + enterprise)
with t() calls, using raw output (<%==) to prevent HTML-encoding of apostrophes
- Translate all mailer subjects to use I18n.t() for locale-aware rendering
- Add comprehensive pt-BR translations for all transactional emails
- Add SSO-specific i18n keys for enterprise confirmation instructions
- Fix ApplicationRecord#to_drop to walk STI hierarchy (e.g. SuperAdmin -> UserDrop)
* fix: address CodeRabbit review feedback
- Use _html suffix for Devise translation keys to prevent XSS while
keeping apostrophes unencoded (Rails escapes interpolations automatically)
- Replace hardcoded English in SLA templates with full_body i18n keys
- Fix _target="blank" typo to target="_blank" in attachment links
- Add i18n for tiktok_disconnect subject and create liquid template
- Extract brand_name to private method in AccountNotificationMailer
* fix: address round 2 review feedback
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
- Create Liquid i18n filter (LiquidFilters::I18nFilter) exposing I18n.t() as `t` filter
- Replace hardcoded English strings in all 26 Liquid email templates with i18n keys
- Replace hardcoded English strings in all 4 Devise ERB email templates with t() calls
- Translate all mailer subjects to use I18n.t() for locale-aware rendering
- Add comprehensive pt-BR translations for all transactional emails
- Fix ApplicationRecord#to_drop to walk STI hierarchy (SuperAdmin -> User)
# Pull Request Template
## Description
Fixes
[CW-4620](https://linear.app/chatwoot/issue/CW-4620/rethinking-custom-domains-in-chatwoot)
<img width="642" height="187" alt="Screenshot 2025-07-29 at 8 17 44 PM"
src="https://github.com/user-attachments/assets/ad2f5dac-4b27-4dce-93ca-6cbba74443fb"
/>
## Type of change
- [x] New feature (non-breaking change which adds functionality)
## How Has This Been Tested?
## Checklist:
- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my code
- [x] I have commented on my code, particularly in hard-to-understand
areas
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged and published in downstream
modules
---------
Co-authored-by: Vishnu Narayanan <iamwishnu@gmail.com>
Co-authored-by: Pranav <pranavrajs@gmail.com>
Co-authored-by: Pranav <pranav@chatwoot.com>
