prefect server in zig

add state_transition_id to flow_runs schema

also fix empirical_policy type: JSONB -> TEXT for consistency with sqlite

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

+2 -1
+2 -1
src/db/schema/postgres.zig
··· 44 \\ work_queue_id TEXT, 45 \\ auto_scheduled INTEGER DEFAULT 0, 46 \\ idempotency_key TEXT, 47 - \\ empirical_policy JSONB DEFAULT '{}' 48 \\) 49 , .{}); 50
··· 44 \\ work_queue_id TEXT, 45 \\ auto_scheduled INTEGER DEFAULT 0, 46 \\ idempotency_key TEXT, 47 + \\ empirical_policy TEXT DEFAULT '{}', 48 + \\ state_transition_id TEXT 49 \\) 50 , .{}); 51