svelte_config_cache.ts

Reads the cache and returns it only if every input still matches stamps. Every kind of miss - absent, corrupt, wrong version, stale - reads the same to the caller, which resolves the config and rewrites.

Snapshots the state of the cache inputs in dir.

Taken by the caller *before* resolving the config, not inside svelte_config_cache_write afterwards: a config edited mid-resolution should leave a stamp that no longer matches, so the next invocation resolves again. Stamping afterwards would pair the old alias with the new state and serve it as fresh.

Bump when SvelteConfigCache's shape changes, or when the meaning of a field does, so caches written by an older Gro self-invalidate instead of being read as the new shape.

Writes the cache for the config that stamps was taken before resolving.

Best effort - a cache that can't be written just means the next invocation resolves again, so a read-only or otherwise unwritable project directory costs speed and nothing else.

The mtime and size of each cache input, or null for one that doesn't exist. Absence is recorded rather than omitted so that *adding* a config file invalidates too.