Fix stale glob cache causing empty tar archives in CacheStorage

[christiango]

Problem

CacheStorage.put() uploads empty (~1KB) tar archives to Azure Blob cache when a worker thread handles multiple tasks that share the same outputGlob and cwd.

Root cause: @lage-run/globby wraps globby with a module-level Map cache keyed on (patterns, options). This cache never expires. When CacheStorage calls globAsync(outputGlob, { cwd }) and a previous call with the same key already ran (e.g., from an earlier task in the same worker thread), the cached result is returned — even though new files have been written to disk since then.

In practice this manifests as:

1. Worker runs task A for a package → put() globs lib/** → caches result ["lib/a.js"]
2. Worker runs task B for the same package → put() globs lib/** → cache hit returns stale ["lib/a.js"] (missing lib/b.js)
3. tar-fs.pack(cwd, { entries: staleList }) produces an incomplete (or empty) tar
4. The broken tar is uploaded to Azure Blob, poisoning the cache for all subsequent CI builds

Fix

• Add globAsyncUncached() and globUncached() exports to @lage-run/globby that call globby/globbySync directly, bypassing the module-level cache.
• Switch CacheStorage (backfill-cache) to use globAsyncUncached in both getHashesFor() and put(), since these always need fresh file system reads.

The existing cached globAsync/glob exports are left unchanged for callers where caching is beneficial (e.g., target graph resolution).

Test

Added cacheStorageGlobStaleness.test.ts — calls put() twice with the same outputGlob + cwd after writing new files between calls. Fails before fix (second put() returns stale single-file list), passes after.