Added 3 new Australian Newsletters (#3295)

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## What does this change?
This PR replaces 3 Australian newsletters (Afternoon Update, Saved For
Later, The Crunch) with (Breaking News, Five Great Reads and Clear Air)
to `/welcome/newsletters`. I've also updated the Morning Mail newsletter
image.

https://trello.com/c/r8UH1fsN
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## How to test
Deployed to CODE and viewed using a VPN.

## Images
| Before | After |
| --- | --- |
|<img width="1908" height="992" alt="Screenshot 2025-12-01 at 13 55 13"
src="https://github.com/user-attachments/assets/8d61fde7-6fba-42e8-8d15-49744af67d73"
/> | <img width="1906" height="993" alt="Screenshot 2025-12-03 at 11 34
07"
src="https://github.com/user-attachments/assets/d1b9554a-6132-4a30-b2ad-3694f1186691"
/> |
<!-- Usually only applicable to UI changes, what did it look like before
and what will it look like after? -->

Author: akinsola-guardian

src/client/assets/newsletters/au-breaking-news.jpg

@@ -1,5 +1,8 @@
 export { default as SATURDAY_EDITION_SMALL_SQUARE_IMAGE } from '@/client/assets/newsletters/saturday-edition-small-square.jpg';
-export { default as MORNING_MAIL_AU_SQUARE_IMAGE } from '@/client/assets/newsletters/au-morning-mail-square.png';
+export { default as MORNING_MAIL_AU_SQUARE_IMAGE } from '@/client/assets/newsletters/au-morning-mail-square.jpg';
+export { default as BREAKING_NEWS_AU_SQUARE_IMAGE } from '@/client/assets/newsletters/au-breaking-news.jpg';
+export { default as FIVE_GREAT_READS_AU_SQUARE_IMAGE } from '@/client/assets/newsletters/au-five-great-reads-square.png';
+export { default as CLEAR_AIR_AU_SQUARE_IMAGE } from '@/client/assets/newsletters/au-clear-air.png';
 export { default as AFTERNOON_UPDATE_AU_SQUARE_IMAGE } from '@/client/assets/newsletters/au-afternoon-update-square.png';
 export { default as SAVED_FOR_LATER_AU_SQUARE_IMAGE } from '@/client/assets/newsletters/au-saved-for-later-square.jpg';
 export { default as THE_CRUNCH_AU_SQUARE_IMAGE } from '@/client/assets/newsletters/au-the-crunch-square.jpg';

src/client/assets/newsletters/au-clear-air.png

@@ -1,6 +1,9 @@
 import { Newsletters, NewslettersWithImages } from '@/shared/model/Newsletter';
 import {
 	AFTERNOON_UPDATE_AU_SQUARE_IMAGE,
+	BREAKING_NEWS_AU_SQUARE_IMAGE,
+	CLEAR_AIR_AU_SQUARE_IMAGE,
+	FIVE_GREAT_READS_AU_SQUARE_IMAGE,
 	HEADLINES_US_SQUARE_IMAGE,
 	MORNING_MAIL_AU_SQUARE_IMAGE,
 	SAVED_FOR_LATER_AU_SQUARE_IMAGE,
@@ -12,6 +15,9 @@ import {
 
 export const NEWSLETTER_IMAGES: Record<NewslettersWithImages, string> = {
 	[Newsletters.MORNING_MAIL_AU]: MORNING_MAIL_AU_SQUARE_IMAGE,
+	[Newsletters.BREAKING_NEWS_AU]: BREAKING_NEWS_AU_SQUARE_IMAGE,
+	[Newsletters.FIVE_GREAT_READS_AU]: FIVE_GREAT_READS_AU_SQUARE_IMAGE,
+	[Newsletters.CLEAR_AIR_AU]: CLEAR_AIR_AU_SQUARE_IMAGE,
 	[Newsletters.AFTERNOON_UPDATE_AU]: AFTERNOON_UPDATE_AU_SQUARE_IMAGE,
 	[Newsletters.SAVED_FOR_LATER_AU]: SAVED_FOR_LATER_AU_SQUARE_IMAGE,
 	[Newsletters.THE_CRUNCH_AU]: THE_CRUNCH_AU_SQUARE_IMAGE,

src/client/assets/newsletters/au-five-great-reads-square.png

@@ -21,9 +21,9 @@ export const NewsletterMap = new Map<
 		'AU',
 		[
 			Newsletters.MORNING_MAIL_AU,
-			Newsletters.AFTERNOON_UPDATE_AU,
-			Newsletters.SAVED_FOR_LATER_AU,
-			Newsletters.THE_CRUNCH_AU,
+			Newsletters.BREAKING_NEWS_AU,
+			Newsletters.FIVE_GREAT_READS_AU,
+			Newsletters.CLEAR_AIR_AU,
 		],
 	],
 	['EU', []],

src/client/assets/newsletters/au-morning-mail-square.jpg

@@ -22,6 +22,9 @@ export const Newsletters = {
 	AFTERNOON_UPDATE_AU: '6023',
 	THE_CRUNCH_AU: '6034',
 	SAVED_FOR_LATER_AU: '6003',
+	BREAKING_NEWS_AU: '6048',
+	FIVE_GREAT_READS_AU: '6019',
+	CLEAR_AIR_AU: '6055',
 	// Registration newsletters
 	SATURDAY_EDITION: '6031',
 	FEAST: '6002',
@@ -34,6 +37,9 @@ export const Newsletters = {
 
 export type NewslettersWithImages =
 	| typeof Newsletters.MORNING_MAIL_AU
+	| typeof Newsletters.BREAKING_NEWS_AU
+	| typeof Newsletters.FIVE_GREAT_READS_AU
+	| typeof Newsletters.CLEAR_AIR_AU
 	| typeof Newsletters.AFTERNOON_UPDATE_AU
 	| typeof Newsletters.SAVED_FOR_LATER_AU
 	| typeof Newsletters.THE_CRUNCH_AU