fix(files): decode markdown refs, scope links to the preview session, drop name= from the sanitizer

Review follow-up on #503. marked percent-encodes link and image destinations, and the rebase pass encoded them a second time, so a space or a CJK character in a file name made file-raw look for a file literally named my%20image.png; refs are now decoded once (a malformed escape is kept as written) and stripped of ?query along with #fragment. Root-relative refs resolve from the workspace root as on GitHub instead of falling through as Codeman URLs. Rebased links carry the preview's own session id and the response-viewer delegate prefers it, so a document opened from another session's attachment card opens its links in that workspace rather than the active tab's.

The sanitizer no longer allows name=: marked never emits it, and <img name="app"> made document.app that image, which every inline onclick="app.…()" handler resolves before the global, so one rendered README broke every viewer button until a reload. Adds the zh-CN strings for the three toolbar titles.

src/web/public/app.js

@@ -2358,7 +2358,9 @@ class CodemanApp {
         ev.preventDefault();
         ev.stopPropagation();
         const filePath = pathLink.dataset.path;
-        if (filePath) this.openFilePreview(filePath, this.activeSessionId);
+        // A rendered document's links name the session the preview was opened
+        // for (_rebaseFilePreviewMarkdownRefs), which need not be the active tab.
+        if (filePath) this.openFilePreview(filePath, pathLink.dataset.sessionId || this.activeSessionId);
         return;
       }