feat: live status-board comment + full-fleet dogfood (#1)

Phase 3: one consolidated, live-updating PR comment aggregating every
model's per-lens progress (queued -> running -> finished + verdict), so
the swarm's progress is visible at a glance and a watcher can tell when
it's done. Opt-in statusWriter in the binary (atomic writes) + a
background status-board.sh renderer wired through entrypoint.sh; default
on, GADFLY_STATUS_BOARD=0 to disable.

Also restores gadfly's dogfood swarm to the full cloud fleet (9 cloud +
M5; M1 dropped as too slow) matching mort, and folds in the 3 real bugs
the swarm found on its own PR (skip-binary stuck-waiting, panic-stuck
lens, busy-loop on bad poll interval). All 36 findings graded via the
gadfly MCP (18 real / 18 false-positive).

gofmt clean, go vet quiet, go build + go test -race green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Co-authored-by: Steve Dudenhoeffer <steve@stevedudenhoeffer.com>
Co-committed-by: Steve Dudenhoeffer <steve@stevedudenhoeffer.com>

scripts/run.sh

@@ -24,7 +24,9 @@
 #   antigravity: `agy` on PATH with credentials already seeded (~/.gemini)
 #
 # Optional:
-#   MAX_DIFF_CHARS  diff truncation cap for the prompt (default 60000)
+#   MAX_DIFF_CHARS     diff truncation cap for the prompt (default 60000)
+#   GADFLY_STATUS_FILE per-model JSON path for the live status board (set by
+#                      entrypoint.sh; empty/unset disables status publishing)
 #
 # This script is advisory: it never fails the job for review content. It exits
 # non-zero only on a usage/configuration error.
@@ -161,6 +163,7 @@ case "$PROVIDER" in
           GADFLY_TITLE="$TITLE" \
           GADFLY_BODY="$BODY" \
           GADFLY_MAX_DIFF_CHARS="$MAX_DIFF_CHARS" \
+          GADFLY_STATUS_FILE="${GADFLY_STATUS_FILE:-}" \
           "$BIN" 2>"$ERR_FILE"
         )"
         rc=$?