Update: 将子项目从 submodule 转为完整内容

- 移除 GovAI, nomifun-tauri, 算力盒子 的 submodule 引用
- 添加所有子项目的完整源代码
- 保留原始 .git 为 .git.bak 备份

nomifun-tauri/docs/guides/model-routing.md

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+# Model Failover Queue
+
+The current feature behind model-routing settings is a **model failover queue**,
+not a credential round-robin pool.
+
+It lets Nomi-engine conversations try a configured sequence of backup models
+when a provider fault is detected. ACP/CLI agents are not included in this
+feature because their provider calls happen inside external runtimes.
+
+## What It Does
+
+- Stores a global default queue under `agent.model_failover`.
+- Allows per-conversation overrides under `extra.model_failover`.
+- Applies only to Nomi-engine conversations.
+- Can be used by IDMM fault-watch flows when that session has failover enabled.
+- Does not distribute load across API keys.
+- Does not make all CLI agents share a common pool.
+
+## When To Use It
+
+Use model failover when a Nomi-engine session should recover from transient
+provider/model faults without requiring manual model switching.
+
+Typical queue:
+
+```text
+primary model -> cheaper backup -> stronger backup -> manual review
+```
+
+The queue is about reliability, not quota aggregation. If every configured
+provider is down or the prompt/tool state is invalid, failover cannot make the
+turn succeed.
+
+## How It Relates To IDMM
+
+IDMM has separate fault and decision watches. Model failover belongs to the
+fault side: when a provider fault is classified as recoverable and failover is
+enabled, IDMM can ask the conversation runtime to retry through the configured
+queue.
+
+AutoWork then sits one layer above both features: it keeps a tagged work queue
+moving, while IDMM/model failover try to keep each claimed turn alive.
+
+## Source Of Truth
+
+- `crates/backend/nomifun-conversation/src/model_failover.rs`
+- `crates/backend/nomifun-conversation/src/failover_seam.rs`
+- `crates/backend/nomifun-app/src/router/model_failover.rs`
+- `crates/backend/nomifun-idmm/src/policy.rs`
+
+Older copies of this page described multi-credential round-robin routing. That
+was not the current implementation and should not be used as operator guidance.