feat(secrets-mcp): 审计页、audit_log user_id、OAuth 登录与仪表盘 footer

- audit_log 增加 user_id；业务写审计透传 user_id
- Web /audit 与侧边栏；Dashboard 版本 footer 贴底（margin-top: auto）
- 停止 API Key 鉴权成功写入登录审计
- 文档、CI、release-check 配套更新

Made-with: Cursor

crates/secrets-core/src/models.rs

@@ -174,6 +174,20 @@ pub struct OauthAccount {
     pub created_at: DateTime<Utc>,
 }
 
+/// A single audit log row, optionally scoped to a business user.
+#[derive(Debug, Serialize, Deserialize, sqlx::FromRow)]
+pub struct AuditLogEntry {
+    pub id: i64,
+    pub user_id: Option<Uuid>,
+    pub action: String,
+    pub namespace: String,
+    pub kind: String,
+    pub name: String,
+    pub detail: Value,
+    pub actor: String,
+    pub created_at: DateTime<Utc>,
+}
+
 // ── TOML ↔ JSON value conversion ──────────────────────────────────────────────
 
 /// Convert a serde_json Value to a toml Value.