* feat: add custom brand name + font feature (v1.2.0)
- Add BRAND_NAME_KEY, BRAND_NAME_FONT_KEY, BRAND_NAME_FONTS whitelist to AccountConfig
- Modify _title.html.erb to render custom brand name with configurable font
- Create _brand_name_form.html.erb partial with text input + font dropdown
- Add brand name form to personalization_settings/show.html.erb
- Add BRAND_NAME keys to PersonalizationSettingsController ALLOWED_KEYS
- Apply brand name header in mailer layout
- Add i18n translations (EN, ES, IT, FR, PT, DE, NL)
- Env override support via DOCUSEAL_CONFIG_BRAND_NAME / DOCUSEAL_CONFIG_BRAND_NAME_FONT
- When brand_name is unset, upstream DocuSeal text renders as before
- When set, configured text renders in chosen font (CSS font-family inline)
* fix: address review — correct font CSS fallback, system-ui quoting, server-side validation
- Add brand_font_css helper to AccountConfig for proper CSS output
- system-ui rendered unquoted; Inter uses sans-serif fallback; script fonts use cursive
- Add server-side validation rejecting fonts not in BRAND_NAME_FONTS whitelist
- Add invalid_font_selection i18n key
* fix: use Rails form helpers for BetterHtml compatibility in brand name and UI visibility forms
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Co-authored-by: Bob Develop <developbob50@gmail.com>