Update lspower to 0.8.4

Editor assessment

A dependency bump stated completely in one line: lspower moves to 0.8.4 within the lsp scope. The chore type matches a routine upgrade, the scope identifies the affected component, and the subject is imperative without a trailing period or ticket junk. No body is needed for a mechanical version bump of this size, so its absence is justified, and the only footer is a well-formed Co-authored-by trailer that adds attribution cleanly. Clear, correct, and publishable as a minor example. For a showcase, one line noting why the bump mattered would be the only possible improvement to an otherwise complete message.