Update structure-assets.md

Minor syntax changes.
Update structure-assets.md
Update structure-extensions.md

Minor syntax changes.
Update runtime-bootstrapping.md

Minor syntax changes.
Update runtime-routing.md

Minor syntax changes.
Update runtime-requests.md

Minor syntax changes.
Update runtime-responses.md

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Update runtime-sessions-cookies.md

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Update runtime-handling-errors.md

Minor syntax changes.
Added note about the fact that both findOne() and one() aren't adding LIMIT 1 to the query
docs/guide updated