fix: Add consecutive_successes column to dispensaries table

Required for stage checkpoint tracking in task handlers

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/migrations/098_dispensary_stage_tracking.sql

@@ -0,0 +1,9 @@
+-- Migration: Add stage tracking columns to dispensaries table
+-- Required for stage checkpoint feature in task handlers
+
+ALTER TABLE dispensaries ADD COLUMN IF NOT EXISTS consecutive_successes INTEGER DEFAULT 0;
+ALTER TABLE dispensaries ADD COLUMN IF NOT EXISTS last_successful_crawl_at TIMESTAMPTZ;
+
+-- Index for finding failing stores
+CREATE INDEX IF NOT EXISTS idx_dispensaries_consecutive_successes
+ON dispensaries(consecutive_successes) WHERE consecutive_successes > 0;