refactor(core): make v2 session inputs event sourced (#30785)

packages/core/src/event/sql.ts

@@ -1,4 +1,4 @@
-import { sqliteTable, text, integer, index } from "drizzle-orm/sqlite-core"
+import { sqliteTable, text, integer, index, uniqueIndex } from "drizzle-orm/sqlite-core"
 import type { EventV2 } from "../event"
 
 export const EventSequenceTable = sqliteTable("event_sequence", {
@@ -19,7 +19,7 @@ export const EventTable = sqliteTable(
     data: text({ mode: "json" }).$type<Record<string, unknown>>().notNull(),
   },
   (table) => [
-    index("event_aggregate_seq_idx").on(table.aggregate_id, table.seq),
+    uniqueIndex("event_aggregate_seq_idx").on(table.aggregate_id, table.seq),
     index("event_aggregate_type_seq_idx").on(table.aggregate_id, table.type, table.seq),
   ],
 )