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/crates/backend/nomifun-db/migrations/015_instance_api_token.sql

@@ -0,0 +1,9 @@
+-- Single-row table holding the SHA-256 hash of the long-lived instance API
+-- token used by the Remote capability front door (`/mcp`). All-or-nothing
+-- trust: one token per instance, hash-only at rest, revocable by deleting the
+-- row. CHECK(id = 1) enforces the singleton invariant.
+CREATE TABLE IF NOT EXISTS instance_api_token (
+    id         INTEGER PRIMARY KEY CHECK (id = 1),
+    token_hash TEXT    NOT NULL,
+    created_at INTEGER NOT NULL
+);