add lemmas for derivable_oo/Nyo/oy_continuous_bnd

[IshiguroYoshihiro]

Motivation for this change

I added lemmas for convenience of derivable_oo/Nyo/oy_continuous_bnd.

• Derive continuity within corresponding interval. The relating lemma is derivable_oo_continuous_bnd_within.
• Restrict the interval, like continuous_subspaceW

Checklist

• added corresponding entries in CHANGELOG_UNRELEASED.md

• added corresponding documentation in the headers

Reference: How to document

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