fix(turbopack) Fix handling of intercept route segments (#82694)
## Fix handling of intercept route segments in HMR
### What?
- Made the routes in `resolve-routes.ts` get lazily initialized, and
only recalculated in development mode to preserve
performance
- Added a test case for HMR with intercept routes
### Why?
This change ensures that intercept route segments (and any other changed
elements of routes), will be recalculated correctly during the
development proecess.
Fixes #PACK-5246