feat: entry update links existing secrets (link_secret_names)

- secrets-core: update flow validates and applies secret links
- secrets-mcp: MCP tool params and UI for managing links on edit
- Align errors and templates; minor crypto/.gitignore tweaks

Made-with: Cursor

crates/secrets-mcp/src/web.rs

@@ -1149,6 +1149,12 @@ fn map_app_error(err: &AppError, lang: UiLang) -> EntryApiError {
                 json!({ "error": tr(lang, "条目已被修改，请刷新后重试", "條目已被修改，請重新整理後重試", "Entry was modified, please refresh and try again") }),
             ),
         ),
+        AppError::DecryptionFailed => (
+            StatusCode::BAD_REQUEST,
+            Json(
+                json!({ "error": tr(lang, "解密失败，请检查密码短语", "解密失敗，請檢查密碼短語", "Decryption failed — please check your passphrase") }),
+            ),
+        ),
         AppError::Internal(_) => {
             tracing::error!(error = %err, "internal error in entry mutation");
             (