feat: add session log usage tracking without proxy

Parse Claude Code JSONL session files (~/.claude/projects/) and Codex
SQLite database (~/.codex/state_5.sqlite) to track API usage without
requiring proxy interception. This enables usage statistics for users
who don't use the proxy feature.

Key changes:
- Add session_usage.rs: incremental JSONL parser with message.id dedup
- Add session_usage_codex.rs: import thread-level token data from Codex
- Add data_source column to proxy_request_logs (proxy/session_log/codex_db)
- Add session_log_sync table for tracking parse offsets
- Background sync every 60s + manual sync via DataSourceBar UI
- Schema migration v7→v8
- i18n support for zh/en/ja

src-tauri/src/commands/usage.rs

@@ -166,6 +166,38 @@ pub fn delete_model_pricing(state: State<'_, AppState>, model_id: String) -> Res
     Ok(())
 }
 
+/// 手动触发会话日志同步
+#[tauri::command]
+pub fn sync_session_usage(
+    state: State<'_, AppState>,
+) -> Result<crate::services::session_usage::SessionSyncResult, AppError> {
+    // 同步 Claude 会话日志
+    let mut result = crate::services::session_usage::sync_claude_session_logs(&state.db)?;
+
+    // 同步 Codex 使用数据
+    match crate::services::session_usage_codex::sync_codex_usage(&state.db) {
+        Ok(codex_result) => {
+            result.imported += codex_result.imported;
+            result.skipped += codex_result.skipped;
+            result.files_scanned += codex_result.files_scanned;
+            result.errors.extend(codex_result.errors);
+        }
+        Err(e) => {
+            result.errors.push(format!("Codex 同步失败: {e}"));
+        }
+    }
+
+    Ok(result)
+}
+
+/// 获取数据来源分布
+#[tauri::command]
+pub fn get_usage_data_sources(
+    state: State<'_, AppState>,
+) -> Result<Vec<crate::services::session_usage::DataSourceSummary>, AppError> {
+    crate::services::session_usage::get_data_source_breakdown(&state.db)
+}
+
 /// 模型定价信息
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
 #[serde(rename_all = "camelCase")]