SPM: add binding usage

[qiancai]

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

• This PR is translated from: SPM: add binding usage docs#21948, planner: add tidb_enable_binding_usage docs#21946
• Other reference link(s):

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• Delete files
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• Need modification after applied to another branch
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[Oreoxmt]

/cc @Oreoxmt

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-11-03 07:35:38.805322978 +0000 UTC m=+82788.248352857: ☑️ agreed by Oreoxmt.

[ti-chi-bot]

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