Starting move of history_stats to integration key for ADR0007

[karwosts]

Proposed change

Allow to define history_stats under history_stats: configuration key instead of sensor:/platform:.

If I understand the rules correctly, this must be done before any future enhancements to the yaml options. ( e.g. from comment: #104907 (review))

Borrowed heavily from #92824 for inspiration.

I think a lot of work could be done still on testing, such as moving more existing tests to the integration key style (right now only have one), but wanted to put this up to get any early feedback if this PR would be welcomed, and if this is the right direction to go.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
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