docs: NIH biosketch round-2 follow-ups handoff

[paulalbert1]

Code-grounded handoff/spec for three biosketch enhancements requested after PR #1187 (the feedback round) deployed and the streaming generate was confirmed working on staging. Spec only — not implemented.

• A. Generation progress bar + rough ETA — upgrade the existing stream from opaque "\n" heartbeats to structured NDJSON progress events (phase boundaries from generateBiosketch), rendered as a determinate-by-phase shadcn progress bar with phase labels + elapsed timer. The largest of the three (changes the response-body contract; client moves off res.json()).
• B. Superuser "view/download prompt & payload" — a superuser-gated debug-payload endpoint that assembles the exact system/user prompt + FACTS projection WITHOUT calling Bedrock, surfaced as a download/dialog. Smallest; independent.
• C. Per-contribution title/subject — a new prompt version v7 (v6 stays byte-pinned) emitting a titled structure, parsed into { title, body }; ripples through generator → parser → BiosketchResult → result card → export → history → provenance coercion (backward-compat for old string[] rows). Gated behind the new v7 default lever.

Sequencing, gotchas, and exact file/function references in the doc. Also re-lists the still-open round-1 operator item (the app_ro SELECT grant for /history).

Full detail: docs/917-biosketch-followups-handoff.md.