feat(dashboard): add forward "what's next" signal + fix upcoming floor

The daily-file bill queue is a backward snapshot, so "upcoming" could only
resurface the latest past day (the 08-31 snapshot read as today's queue) and
there was no "what is scheduled next." leginfo bill status/history are
backward-only, so the genuine future-dated signal is the chambers' "upcoming
events" calendars.

- api.py: floor the "upcoming" view at *today* (not the DB max date) when no
  as_of is pinned; surface next_legislative_day + scheduled_events (next 7
  days) on /bills. Add _today_iso / _next_legislative_day / _scheduled_events,
  all degrading to a recess marker / [] (never 5xx).
- relational.py: schema v2 adds the scheduled_events table +
  store_scheduled_events (idempotent per-day refresh), load_scheduled_events,
  next_legislative_day.
- parsers.py: parse_events_page + classify_event_kind for the chamber events
  calendar; skip empty-title rows (decompose the <time> before the fallback).
- ingest.py + cli.py: --store-events lane (cache-first, recess-safe) that
  parses the calendar HTML into scheduled_events.
- sources.py + config.yaml: register assembly_events / senate_events
  (kind: events, empty_is_ok: true).
- run_ingest.sh: run the events lane after the daily-file lane as non-fatal
  (skippable via CALI_SCRAPER_SKIP_EVENTS=1); daily-file exit still gates cron.
- frontend: "Next legislative day" line + "What's next · next 7 days" band
  with honest recess empty states.
- DASHBOARD.md: document the forward signal + known limitations (leginfo
  backward-only gap, recess empty state, 08-31 snapshot is analysis-only).
- tests: 5 new API tests + 18 parse-events tests; 170 pass, 92% coverage.

scraper/dashboard/static/style.css

@@ -139,6 +139,19 @@ button.chip-toggle { min-width: 120px; }
 .band-title .count { color: var(--ink); font-weight: 700; }
 #personal-band .band-title { color: var(--accent); }
 
+/* ---- forward "what's next" band (scheduled_events) ---- */
+.next-band { background: #fbfcff; }
+.next-band .band-title { color: var(--accent); }
+.ev-row {
+    display: grid; grid-template-columns: 120px 1fr auto;
+    gap: 10px; align-items: baseline;
+    padding: 8px 8px 8px 0; border-bottom: 1px solid var(--border);
+}
+.ev-date { color: var(--muted); font-size: 13px; white-space: nowrap; }
+.ev-main { font-weight: 600; }
+.chip.ev-kind { background: #eef3fb; color: var(--asm); border-color: #cdd9ee; }
+#freshness-next-day { white-space: nowrap; }
+
 .day-heading {
    font-size: 13px; color: var(--muted); margin: 14px 0 6px;
    padding-bottom: 4px; border-bottom: 1px solid var(--border); }