agent page restructure:
- send form moves into the terminal panel as a prompt-style row beneath
the live tail (status line stays above so it still reads as a header).
- live panel + prompt share a single bordered 'terminal-wrap' box.
- harness-alive / login-state status lines drop their decorative ascii
bookends; just a leading dot/glyph remains.
- banner gradient is now a real css gradient with a shimmer animation
toggled by an .active class. turn_start adds it, turn_end removes it.
dashboard side mirrors this: each broker sse event nudges a 4s
shimmer window.
- dashboard container rows drop their static ▓█▓▒░ / ▒░▒░░ glyph
prefixes; the role chips already disambiguate m1nd vs ag3nt.
- empty-state placeholders drop the ▓ bookends.
terminal pre-fill: hive-ag3nt::events::Bus grows a 500-event ring
buffer; new GET /events/history endpoint returns it. The agent JS
fetches history before opening the SSE stream so opening the page mid-
turn shows the last N events instead of a blank panel. The replay
walks turn_start/turn_end pairs to seed the banner-active state
correctly if a turn was still open.
new mcp tool on the manager surface that queues a question on the
dashboard and returns the question id immediately. operator submits an
answer via /answer-question/<id>; the dashboard fires
HelperEvent::OperatorAnswered { id, question, answer } into the manager
inbox so the next turn picks it up.
also: fix async-form button stuck on spinner after successful submit
(refreshState skipped re-rendering, so the button was never re-enabled).
