Flutter app language update

The Flutter mobile app is built with FVM 3.38.5 and targets both iOS and Android. The backend is
Magento 2 with 32 store views covering up to 32 languages and locales.

The language infrastructure code is already implemented in the app.
This role covers two outstanding deliverables only:

1. Language switcher UI -- add a visible in-app dropdown so the user
can change language and locale at runtime.

2. API localisation -- update 35 existing API calls so each one passes
the correct country-specific store code, locale, and currency to
the Magento REST API.

No architectural decisions are to be made independently. All changes
must follow the existing patterns in the codebase. All questions must
be escalated before proceeding.


SCOPE OF WORK
--------------

TASK 1 -- LANGUAGE SWITCHER DROPDOWN

The app already has locale/language state management in place.
The contractor must:

- Add a language/country switcher dropdown widget to the appropriate
screen (to be agreed with the project lead before starting).
- The dropdown must list all supported store locales in the correct
display format
- Selecting a language must update the app locale state, persist the
selection across sessions, and reload the current view.
- The switcher must respect the 32 supported store views and their
corresponding locale codes.
- UI will remain the same this is inly a translation of the app


TASK 2 -- API CALL LOCALISATION (35 CALLS)

The app makes 35 API calls to the Magento 2 REST API. Currently
these calls do not pass the correct country-specific store code
and locale parameters. Each call must be updated to:

- Pass the correct Magento store code in the API path or header
based on the user's currently selected locale.
- Pass the correct locale and currency where the API supports it.
- Derive all store-specific values from a single source of truth
(the existing locale/store mapping already in the codebase).
- Never hardcode a store code, locale, or currency in any API call.
- All 35 calls must be updated -- no partial completion accepted.

The contractor must audit all 35 calls, document what each one does,
and confirm the mapping before making any change. A list must be
submitted to the project lead for review before coding begins.


TECHNICAL REQUIREMENTS
-----------------------
- Flutter FVM 3.38.5


DELIVERABLES
-------------
1. Pre-work: List of all 35 API calls with current behaviour and
proposed store code mapping -- submitted for review before coding.
2. Language switcher dropdown -- fully working, tested on iOS and
Android, matching existing UI design.
3. All 35 API calls updated and verified against each locale.
4. Pull request per task raised against the development branch.
5. Brief notes per PR explaining what changed and how to test.