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/src/models/conversation.rs

@@ -0,0 +1,38 @@
+use nomifun_common::TimestampMs;
+use serde::{Deserialize, Serialize};
+
+/// Row mapping for the `conversations` table.
+///
+/// Enum-like fields (`type`, `status`, `source`) are stored as TEXT strings.
+/// The service layer converts them to/from `nomifun_common` enums
+/// (`AgentType`, `ConversationStatus`, `ConversationSource`).
+///
+/// JSON fields (`extra`, `model`) are stored as TEXT in SQLite and
+/// deserialized by the service layer.
+#[derive(Debug, Clone, Serialize, Deserialize, sqlx::FromRow)]
+pub struct ConversationRow {
+    pub id: i64,
+    pub user_id: String,
+    pub name: String,
+    /// Agent type string (e.g. "gemini", "acp", "remote").
+    #[sqlx(rename = "type")]
+    pub r#type: String,
+    /// JSON object: type-specific extra data.
+    pub extra: String,
+    /// JSON object: `ProviderWithModel` serialized.
+    pub model: Option<String>,
+    /// One of: "pending", "running", "finished". NULL in legacy rows.
+    pub status: Option<String>,
+    /// One of: "nomifun", "telegram", "lark", "dingtalk", "weixin".
+    pub source: Option<String>,
+    /// Channel isolation ID (e.g. "user:xxx", "group:xxx").
+    pub channel_chat_id: Option<String>,
+    /// Whether this conversation is pinned (SQLite INTEGER 0/1).
+    pub pinned: bool,
+    pub pinned_at: Option<TimestampMs>,
+    /// The cron job that created this conversation (was `extra.cronJobId`;
+    /// now a real nullable FK column to `cron_jobs`).
+    pub cron_job_id: Option<String>,
+    pub created_at: TimestampMs,
+    pub updated_at: TimestampMs,
+}