feat(i18n): add Portuguese (Portugal) locale

[salvadord18]

Adds Portuguese (Portugal) localization support using the existing PT-PT
translations where available, with the remaining strings translated
consistently.

Changes

• Add pt-PT translations
• Register the new locale in the application settings
• Expose Portuguese (Portugal) in the locale picker
• Update the locale map
• Preserve translation placeholders and inline markup from the English source

Testing

• Validated the JSON structure
• Confirmed that all translation placeholders match the English source
• Confirmed that inline markup matches the English source
• Started the application locally using the development server
• Manually verified that the pt-PT locale loads successfully
• Manually verified the Portuguese (Portugal) translations on the unauthenticated profile page

The authenticated interface and locale picker could not be verified because
local Trakt API credentials were not configured.

Screenshots

Before — Portuguese (Portugal) unavailable

Portuguese (Portugal) is not currently available in the language selector on
the deployed website.

Current deployment — Portuguese (Brazil)

The deployed website currently displays the unauthenticated profile page using
Portuguese (Brazil), as Portuguese (Portugal) is not available.

After — Portuguese (Portugal) local implementation

The pt-PT locale loads successfully and the Portuguese (Portugal)
translations are displayed on the unauthenticated profile page in the local
development build.

Documentation

No documentation changes are required for this localization update. The new
locale follows the same structure and conventions as the existing supported
locales.

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