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

• [X] My pull request adheres to the code style of this project
• [X] My code requires changes to the documentation
• [X] I have updated the documentation as required
• [X] 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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[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 https://github.com/keephq/keep/pull/5438/commits/ee225e79c9e8b4ccd272695b2981fb5647a67b67

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 https://github.com/keephq/keep/pull/5366#issuecomment-3405658571.

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

[shahargl]

@Aze331 it doesn't really matter. I just want test to pass so i can merge :)