Start: Ssr doesn't reflect changes with `bundledDev: true`

Which project does this relate to?

Start

Describe the bug

Ssr content does not appear to reflect changes to source files when the vite config experimental: { bundledDev: true } is enabled.

Hmr updates to the files does appear to work as expected. It is only the server side content that doesn't update.

Complete minimal reproducer

https://github.com/CamBurris/tanstack-start-bundled-dev

Steps to Reproduce the Bug

1. Clone repo and install deps
2. Start with npm run dev
3. Make a change to a file that will appear on the page. I used routes/index.tsx.
4. You will see the page updated via hmr to reflect the change.
5. Reload the page in the browser. You will see the ssr version of the page is not updated.

Expected behavior

Ssr version of page should reflect changes to files.

Screenshots or Videos

No response

Platform

• Router / Start Version: 1.170.11
• OS: macOS
• Browser: Chrome
• Browser Version: 148
• Bundler: vite
• Bundler Version: 8.0.16

Additional context

No response

Start with the linked minimal reproducer and its Vite config using experimental: { bundledDev: true }; run npm run dev and edit routes/index.tsx. Compare the HMR result with a browser reload, then trace the bundled development SSR entry point to identify why server-rendered content stays stale. Done means reloads reflect source changes while HMR continues to work.