v15.4.2-canary.11

Core Changes

• [sourcemaps] Try VM for retrieving source maps first: #81869
• [devtools] save user config inside .next/cache: #81807
• Server: Remove unused code: #81886
• refactor: encapsulate content type within RenderResult: #81861
• refactor: handle null RenderResult responses gracefully: #81895

Misc Changes

• Turbopack: fix unhelpful error message when deleting folder fails: #81718

Credits

Huge thanks to @eps1lon, @devjiwonchoi, @timneutkens, @wyattjoh, and @sokra for helping!