Backend/push: Tweak host request notif for clarity

[tristanlabelle]

Based on feedback counting the number of days as the number of nights + 1 is confusing. Change to counting the number of nights.

I decided against changing the string key since the placeholders didn't change. Translators will need to follow-up.

Testing

N/A - unfortunately this path is not easily testable.

Backend checklist

• Added tests for any new code or added a regression test if fixing a bug
• Run the backend locally and it works
• Added migrations if there are any database changes, rebased onto develop if necessary for linear migration history

For maintainers

• Maintainers can push commits to my branch
• Maintainers can merge this PR for me

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Project	Deployment	Actions	Updated (UTC)
couchers	Ready	Preview	May 9, 2026 2:15pm

[github-actions]

📝 Release Notes

This PR does not need to be included in release notes.

Reason: This is a minor wording/notification clarity tweak to an existing push notification, not a significant user-facing feature, major UX improvement, or important bug fix affecting core functionality.

🤖 Bot Debug Information

Model: couchers.openai.gpt-5.4
Decision: exclude
Reasoning: This is a minor wording/notification clarity tweak to an existing push notification, not a significant user-facing feature, major UX improvement, or important bug fix affecting core functionality.