dashboard: add note about disk warnings

[hfxsd]

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What is the related PR or file link(s)?

• This PR is translated from:dashboard: add note about disk warnings docs#21863
• Other reference link(s):

Do your changes match any of the following descriptions?

• Delete files
• Change aliases
• Need modification after applied to another branch
• Might cause conflicts after applied to another branch

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-10-15 07:31:24.335471691 +0000 UTC m=+252190.412724250: ☑️ agreed by Oreoxmt.

[hfxsd]

/approve

[hfxsd]

/approve

[hfxsd]

/approve

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hfxsd

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.1: #21005.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.5: #21006.