Add source-map-grabber.ts to provide utilities for extracting source map data from bippy's cache and specified URLs.

This file implements functions to retrieve filename-to-fileContent mappings from bippy's sourceMapCache and by fetching source maps from given URLs, supporting both standard and indexed source maps, and handling WeakRef entries in the cache.

Summary by cubic

Add source map grabbing utilities and integrate them into getElementContext to show inline source snippets in stack output for Next apps. Also freeze toolbar animations and pseudo states during hover, and disable interactions when collapsed, to reduce flicker while inspecting.

• New Features

  • getSourceMapDataFromCache, getSourceMapDataForUrl, getSourceMapDataFromScripts, and getSourceMapData to merge cached and fetched data.
  • getElementContext: when source maps are available, renders a small source snippet around the frame line with file:line[:col], using normalized filenames and handling indexed maps.
  • Caches merged source map data in-memory to avoid refetching across calls.

• Dependencies

  • Added TypeScript ^5.9.3 to devDependencies; updated pnpm lockfile.

^{Written for commit 9e2fe65. Summary will update on new commits.}