#3792 Docs: dashboard Approvals view shows run context, reason and per-viewer decide state

The dashboard's Approvals view changes with swamp-club#3697, and content/manual/reference/swamp-serve/dashboard.md (section "Approvals") should describe it:

• Each pending gate shows who started the run ("by ", the run's recorded initiatedBy), the linked short run ID and the wait time; the prompt keeps its line breaks.
• Expanding a gate shows "Started by" and the run's inputs, as plain text.
• Approve and Reject ask for confirmation with an optional reason, recorded on the run with decidedBy. The local dashboard passes it to swamp workflow approve|reject --reason.
• A viewer who does not hold approve on the workflow sees the buttons disabled with "You don't hold approve on this workflow". Serve only tells each viewer about their own permission; it never lists who else may approve. run implies approve unless --approve-requires-explicit-grant is set.
• After a decision the card shows "Approved by …" until the listing refreshes, and a notice says what happens next: serve is resuming the run, the run waits for Resume under Awaiting resume, or other gates are still pending. A gate already decided elsewhere is reported as such, not as a failure.

The "approved — serve is resuming the run" sentence in that section should become the new notice wording.