weichen
136e93bf1d
Why: X3 must share one Backend surface with the X1 context and X2 audit candidates while current main now owns account migrations 32-34.
Evidence: go test -p 1 ./... and go build ./... passed on the merged tree; isolated PostgreSQL project audit, migration, and work-context tests passed against a temporary instance. Default parallel go test ./... had only the unrelated sandbox orphan timing test fail; its isolated ten-run replay passed.
Impact: Preserve account migrations 32-34, place X1/X2 migrations at 35-43, and retain account-effective write guards alongside project audit/context behavior. X3 observer remains a contract only.
Refs: TT-C01-TT-C04, TT-A01-TT-A04, TT-N03, TT-R01; combination probe d9b00c2
Agent-System-Backend
对话系统后端：Go 模块化单体，默认构建为单二进制（go:embed 内嵌前端与嵌入式 SQLite 存储）。组合 Agent-Native / Agent-Squad / Agent-Intent 生态，依赖 agent-system-core 契约。
契约与架构见 Agent-System-Documents 设计方案与架构文档；开发规范见 development-guidelines（Dev 仓 development/guidelines）。本仓为 Agent-System 多仓组合的组成部分。