Deploy main eacf1e7 to prod

Replaces #559, which conflicted.

Model: opus-5-5

internal/db/migrations/main/000_migration.sql

@@ -0,0 +1,9 @@
+-- Migration 000: the table recording which migrations this file has
+-- had. Applied before the others; it records itself.
+
+CREATE TABLE IF NOT EXISTS schema_migrations (
+    version INTEGER PRIMARY KEY,
+    applied_at DATETIME DEFAULT CURRENT_TIMESTAMP
+);
+
+INSERT OR IGNORE INTO schema_migrations (version) VALUES (0);