fix: provide stable Monaco model path in file editor (#2781)

rules/git-workflow.md

@@ -6,6 +6,16 @@ When pushing changes and creating PRs:
 2. If the branch hasn't been pushed before, default to pushing to `origin` (the fork `wwwillchen/dyad`), then create a PR from the fork to the upstream repo (`dyad-sh/dyad`).
 3. If you cannot push to the fork due to permissions, push directly to `upstream` (`dyad-sh/dyad`) as a last resort.
 
+## `gh pr create` branch detection
+
+If `gh pr create` says `you must first push the current branch to a remote` even though `git push -u` succeeded, create the PR with an explicit head ref:
+
+```bash
+gh pr create --head <owner>:<branch> ...
+```
+
+This can happen when remotes are configured in a non-fork layout and `gh` fails to infer the branch mapping.
+
 ## Skipping automated review
 
 Add `#skip-bugbot` to the PR description for trivial PRs that won't affect end-users, such as:

src/components/preview_panel/FileEditor.tsx

@@ -139,6 +139,10 @@ export const FileEditor = ({
     (theme === "system" &&
       window.matchMedia("(prefers-color-scheme: dark)").matches);
   const editorTheme = isDarkMode ? "dyad-dark" : "dyad-light";
+  const modelPath = React.useMemo(() => {
+    const normalizedPath = filePath.replace(/^\/+/, "");
+    return `file:///app-${appId ?? "unknown"}/${encodeURI(normalizedPath)}`;
+  }, [appId, filePath]);
 
   // Navigate to a specific line in the editor
   const navigateToLine = React.useCallback((line: number | null) => {
@@ -260,6 +264,7 @@ export const FileEditor = ({
       <div className="flex-1 overflow-hidden">
         <Editor
           height="100%"
+          path={modelPath}
           defaultLanguage={getLanguage(filePath)}
           value={value}
           theme={editorTheme}