Adds a compare mode to the bundle analyzer. When the user picks a
historical snapshot from the new baseline picker in the top bar, the UI
switches into compare mode: routes are diff'd by name and size, and the
per-route view shows a `DiffTreemap` that colors each source tile by its
change status (added/removed/grew/shrank/unchanged).
The compare sidebar shows the import chain for the selected tile on
either the baseline ("A") or current ("B") side. Route totals are
fetched in parallel so the route picker can sort by largest impact and
classify routes as `changed`/`identical` rather than just name-presence.
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Co-authored-by: vercel-fleet-prod[bot] <318278635+vercel-fleet-prod[bot]@users.noreply.github.com>
Co-authored-by: Will Binns-Smith <755844+wbinnssmith@users.noreply.github.com>
This:
- Removes the uncompressed/compressed toggle in favor of just using
compressed sizes when sizing treemap nodes
- Fixes the width of the client/server and file type triggers so that
they don't reflow horizontally when their content changes
Fixes PACK-6295
Fixes PACK-6298
Will Binns-Smith
