Add tikv-br docs

[haojinming]

Signed-off-by: haojinming jinming.hao@pingcap.com

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• This PR is translated from: Add tikv-br docs docs-cn#12188
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[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• hfxsd
• shichun-0415

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[CLAassistant]

All committers have signed the CLA.

[shichun-0415]

Could you please help synchronize the change to the Chinese version? Thank you

[haojinming]

Could you please help synchronize the change to the Chinese version? Thank you
Chinese docs PR is here:
pingcap/docs-cn#12188 . PTAL~ thanks.

[pingyu]

Suggest to simply as following:

TiKV and PD can constitute a KV database when used without TiDB, which is called RawKV. TiKV-BR supports data backup and restore for products that use RawKV. Please see [TiKV-BR User Docs] for detail.

API v2 is another feature, and in general users use API v2 first, and then they need the BR.
The CDC is also another feature for a different scenario. I think it's not suitable to mention it here.

[pingyu]

LGTM~

[shichun-0415]

LGTM

[shichun-0415]

/status LGT2

[hfxsd]

Rest LGTM

[shichun-0415]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: a58734c