Handle subscription cancellation

[MiSikora]

Description

This PR adds logic for handling subscription cancellation.

Testing Instructions

Note

Enable WINBACK flag in the code and test this with the release variant.

Paddle subscription

1. Sign in with this account: p1737624995796789-slack-C028JAG44VD
2. Go to Account Details.
3. Tap on Yes, Cancel my Subscription.
4. You should see FAQ about how to cancel a subscription.

Google subscription

1. Sign in with an account that has a Google subscription.
2. Go to Account Details.
3. Tap on Yes, Cancel my Subscription.
4. You should see your subscription in the Play Store.

Checklist

• If this is a user-facing change, I have added an entry in CHANGELOG.md
• Ensure the linter passes (./gradlew spotlessApply to automatically apply formatting/linting)
• I have considered whether it makes sense to add tests for my changes
• All strings that need to be localized are in modules/services/localization/src/main/res/values/strings.xml
• Any jetpack compose components I added or changed are covered by compose previews
• I have updated (or requested that someone edit) the spreadsheet to reflect any new or changed analytics.

[dangermattic]

	1 Error
🚫	This PR is tagged with do not merge label(s).

	1 Warning
⚠️	Class AccountDetailsViewModel is missing tests, but unit-tests-exemption label was set to ignore this.

Generated by 🚫 Danger

[wpmobilebot]

📲 You can test the changes from this Pull Request in 📱 Mobile by scanning the QR code below to install the corresponding build.

	App Name	📱 Mobile
	Build Type	debugProd
	Commit	3b99d8f
	Direct Download	pocketcasts-app-prototype-build-pr3475-3b99d8f.apk

📲 You can test the changes from this Pull Request in 🚗 Automotive by scanning the QR code below to install the corresponding build.

	App Name	🚗 Automotive
	Build Type	debugProd
	Commit	3b99d8f
	Direct Download	pocketcasts-automotive-prototype-build-pr3475-3b99d8f.apk

📲 You can test the changes from this Pull Request in ⌚ Wear by scanning the QR code below to install the corresponding build.

	App Name	⌚ Wear
	Build Type	debugProd
	Commit	3b99d8f
	Direct Download	pocketcasts-wear-prototype-build-pr3475-3b99d8f.apk