Docs: hx-swap-oob clarity. Removed excess from hx-swap short desc.

[gnat]

Before / After

• Clarified hx-swap-oob vs hx-select-oob
• Consistent wording of "out of band" in hx-swap-oob and hx-select-oob
• Removed excess information from hx-swap short description.

[Telroshan]

Hey @gnat , following up late on this (sorry about that!) If you are still interested in this doc change, could you update & resolve conflicts with master? Thanks!

[1cg]

@gnat pinging again for a conflict resolution (sorry I let it sit so long)

[gnat]

Gonna close this to get it off the table.