docs: 全面按当前源码更新文档 + 删除已过时文档

## 删除（内容已落地/已被替换，保留只会误导）
- demo.md ................... failback 与 recoverydiag 均已实现，0 引用
- docs/defect-qq-output-send-loop.md .. 已修复（本身也标了「已修复」），0 引用
- docs/embedding-comparison.md ....... 一次性选型报告，仅被 agent 产物引用
- docs/zh/plan.md ............ 描述的旧 nav 布局已重写、死配置已清，全部完成
- docs/zh/plugin-migration-plan.md ... 迁移已上生产，纯过程稿（Part 0~6 全完成）

## 更新（按当前源码核对）
- assets/docs/{zh,en}/ARCHITECTURE.md（README 指向的用户文档，最重要）：
  把只讲 cancel/intercept 的旧「中断机制」章节重写为「输入调度器与中断机制」——
  补上两类别 + 四级中断（L1~L4，默认 L1、外部插件 L4 夹到 L3）+ 抢占/挂起/中断栈
  + 饥饿防护（PreemptCount 提升，封顶 L4）+ 抢占冷却（2s）+ 停止语义（cancelBudget）
  + 驻留子/分诊助手/残余任务；新增「上下文预算」章节（窗口 ≠ 工作面，600K 封顶，
  预算是上限非填充目标）。中英章节数现已对齐（各 13 节）。
- assets/docs/{zh,en}/PLUGIN_DEV.md：插件示例表补 6 个缺失项
  （acp/deepsearch/plugindev/recoverydiag/vanblog/vikunja）；qq 工具数 17 → 20（实测）。
- README.md / README_EN.md：补 v1.3.x 线（此前只到 v1.2.0，而 1.3.x 已发布 12 个 patch）——
  驻留式子 agent、输出通道寻址、输入调度器、轻量内核 profile、积压及时反馈。
- plan.md：开头两个「⚠️ 紧急/正在持续污染」是过期告警（实测  残留 = 0），
  改为「已解决」并加文档定位说明；§13 仍是活跃路线图故保留。
- docs/zh/plugin-interface-matrix.md + 两处源码注释：清理指向已删文档的断链。

全仓 md 断链检查：仅剩 1 处，位于 third_party 的 oh_modules（第三方依赖，非本项目）。

README_EN.md

@@ -184,6 +184,31 @@ External plugin development: see [homeagent-sdk](https://gitcode.com/JianFeeeee/
 
 ## Project Status
 
+**v1.3.x line** (v1.3.1–v1.3.12, latest released) — **resident sub-agents** + **input scheduler rework**.
+
+- **Resident sub-agents**: the kernel can station lightweight-kernel child agents (their own
+  scheduler, their own temp graph memory, sharing the channel registry). The parent dispatches
+  and collects work via `resident_agents` (list/create/send/inspect/compress/reclaim/destroy).
+  An inputch can be assigned to a child, so input is routed to it **before entering the kernel**.
+- **Output channels addressable to a specific agent**: the `AllowedOutputs` grant set
+  (consistent across all three filter points) lets parent/child deliver to each other;
+  device capabilities became output channels too (one `device/<id>` per device).
+- **Input scheduler**: two task classes (queued/interrupt) + four interrupt levels (L1–L4)
+  + preempt/suspend/resume/interrupt-stack; same level never preempts same level, with a
+  starvation guard and preemption cooldown. L4 belongs only to the kernel and kernel-level
+  plugins (e.g. the WebUI stop button).
+- **Lightweight kernel profile**: a child's memory surface narrows to "conventional context
+  + graph memory" (narrow interface; the main graph opens as a query_only handle, writes go
+  to its own temp instance).
+- **Backlog timely feedback** (later in the line): when the main agent is busy for a long time,
+  the kernel hands queued input to a temporary **triage assistant** — simple items are handled
+  directly, items needing the main agent get an immediate "busy, please wait", so users no
+  longer wait 10+ minutes in silence.
+- Fixed a batch of real defects: inbound inputch (`child/<id>`) registration leak on resident
+  destruction, a child's round count always showing 0 (`info()` never filled it), an empty
+  child-side childIO (output channels not inherited), device heartbeat pong missing Flush
+  (dropping every 60s), and Lua plugin bridge alignment with SDK 1.3.0.
+
 **v1.2.0** — unified multimodal vector space, media promoted to first-class graph memory, and the whole data plane moved into shared memory.
 
 - **Model-neutral unified embedding space**: the kernel no longer adapts to any specific model.