feat: add webhook setup instructions via webhook_description for UptimeKuma

[Aze331]

📑 Description

This PR updates the UptimekumaProvider with a webhook_description to guide users through configuring Uptime Kuma to send alerts to Keep.

The webhook_template remains an empty string, because Uptime Kuma’s preset JSON works out-of-the-box with Keep’s webhook endpoint. There are no functional or behavioral changes to the provider.

✅ Checks

• My pull request adheres to the code style of this project
• My code requires changes to the documentation
• I have updated the documentation as required
• All the tests have passed

ℹ Additional Information

• This is metadata/UI guidance only; it does not alter alert ingestion or STATUS_MAP behavior.
• The {keep_webhook_api_url_with_auth} placeholder is consistent with other providers (e.g., Pingdom) and is resolved by Keep at runtime.

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Skipped: This PR does not target one of your configured branches: (refactor/2512-nextjs-15)

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[shahargl]

Hey! thanks for opening this PR!

We have some problem with the CI/CD. Going to handle it soon and let this PR in :)

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Project	Deployment	Preview	Comments	Updated (UTC)
keep	Ready	Preview	Comment	Nov 16, 2025 7:54am

[Aze331]

Hey @shahargl , thanks for fixing the problem, I realize now that I made a mistake in ee225e7

The file was not generated due to my ignorance,
import AutoGeneratedSnippet from '/snippets/providers/uptimekuma-snippet-autogenerated.mdx';

Saw that I should execute python3 scripts/docs_render_provider_snippets.py from #5366 (comment).

Should I fix it in this PR or create a new one?