VoxyWatch v2.126.1

Fixed — inflated concurrency ("Simultaneous calls") + startup blocked by indexes in schema.sql

• Inflated concurrency (~24k vs ~hundreds real): the simultaneous-calls series is a Σstarts − Σends ledger. The rollup's ended query was still slow (70s → cancelled) because the planner preferred the smaller old index idx_calls_ended_ts (no call_result) over v2.126's covering idx_calls_ended_cr → ended was chronically undercounted → the ledger subtracted too little and concurrency grew unbounded. Fix: drop idx_calls_ended_ts (the covering replaces it and forces the index-only scan); the rollup backfill re-populates ended → concurrency rebalances within hours.
• Portal startup blocked during the v2.126 update: the covering indexes were in schema.sql, which the updater applies in a BLOCKING way → creating several GB of index over the already-populated calls froze startup ~10 min (capture was never affected; separate service). Fix: large indexes are created ONLY in ensureSearchIndex() with CREATE INDEX CONCURRENTLY (not in schema.sql) → startup no longer blocks on large installs.