[Snap] Implement Localisation Settings

[benfrancis]

STR:

• In web interface navigate to Main Menu -> Settings - Localisation

Expected:

• Country, Timezone, Language, and Temperature Units preferences displayed
• Can change each preference by selecting an item in the dropdown

Actual:

• Country and Timezone dropdowns are unpopulated
• Language and Temperature dropdowns are populated but changing them doesn't seem to have any effect

From the browser console when setting Language:

Uncaught (in promise) Error: 500
    getJson api.ts:44
    promise callback*getJson api.ts:42
    getPushKey api.ts:474
    r notifications.js:23
    i thing-model.js:324
    a notifications.js:16
    promise callback*i thing-model.js:324
    a notifications.js:16
    s notifications.js:16
    s notifications.js:16
    onReady notifications.js:16
    promise callback*96710 app.js:619
    Webpack 3
api.ts:44:14

Also noticed network errors in the browser console during first time setup:

Uncaught (in promise) TypeError: NetworkError when attempting to fetch resource.

XHRPUT
http://localhost:8080/settings/localization/language
[HTTP/1.1 401 Unauthorized 1ms]

XHRGET
http://localhost:8080/settings/localization/units
[HTTP/1.1 401 Unauthorized 2ms]

Uncaught (in promise) Error: 401
    getJson http://localhost:8080/bundle/6f3f2b9653370ff453ac-app.js:8
    promise callback*getJson http://localhost:8080/bundle/6f3f2b9653370ff453ac-app.js:8
    getUnits http://localhost:8080/bundle/6f3f2b9653370ff453ac-app.js:8
    e http://localhost:8080/bundle/6f3f2b9653370ff453ac-app.js:8
    promise callback*e http://localhost:8080/bundle/6f3f2b9653370ff453ac-app.js:8
    96710 http://localhost:8080/bundle/6f3f2b9653370ff453ac-app.js:8
    n http://localhost:8080/bundle/6f3f2b9653370ff453ac-app.js:8
    <anonymous> http://localhost:8080/bundle/6f3f2b9653370ff453ac-app.js:8
    <anonymous> http://localhost:8080/bundle/6f3f2b9653370ff453ac-app.js:8
6f3f2b9653370ff453ac-app.js:8:946120

XHRGET
http://localhost:8080/settings/localization/language
[HTTP/1.1 401 Unauthorized 2ms]

On one occasion I also noticed an error in run-app.log after creating a username and password during first time setup:

2024-08-20 19:00:20.691 ERROR : Failed to set localization.language to 'en-GB'