perf(graperank): adaptive idle-EOSE cutoff (--eose-idle-ms)

Measured: relays deliver their events in ~0.6s then sit ~4.6s (86% of drain wall)
before sending EOSE — mostly relay-side (our pipeline adds only ~200ms). So instead
of waiting the full 10s fast window then parking, close a drain that has delivered
>=1 event and then gone silent for eoseIdleMs, treating it as complete ("eose-idle").

awaitTerminalOrQuiescent: the idle timer arms only AFTER the first event, so a relay
merely slow to answer still gets the full timeoutMs and is never cut prematurely; a
still-streaming relay keeps resetting the window. eose-idle paginates if the page was
capped and clears timeout strikes (it delivered), but joins notAnswered (no clean
EOSE, so its missing authors are retried elsewhere). Off by default (eoseIdleMs=0),
CLI --eose-idle-ms, so it can be A/B'd against the plain fast window.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MSW59hJtP4Yn8fnRUxc7F5

cli/src/main/kotlin/com/vitorpamplona/amethyst/cli/commands/GrapeRankCommand.kt

@@ -464,6 +464,9 @@ object GrapeRankCommand {
                     insertBatchSize = args.intFlag("insert-batch", 500),
                     drainConcurrency = args.intFlag("drain-concurrency", 24),
                     timeoutEvictStrikes = args.intFlag("timeout-evict", 3),
+                    // Adaptive EOSE cutoff: close a drain that delivered then fell silent
+                    // this many ms, instead of waiting the full fast window. 0 = off.
+                    eoseIdleMs = args.longFlag("eose-idle-ms", 0L),
                     // Cheap TCP reachability pre-probe (--no-probe to disable). No Tor
                     // transport here, so .onion relays are skipped on sight.
                     reachabilityProbe = if (args.bool("no-probe")) null else ::tcpReachable,