Function evictToQuota

evictToQuota(
db: IDBDatabase | null | undefined,
maxBytes: number,
): Promise<EvictionResult>
Evicts the least-recently-cached records until the "layers" store fits within maxBytes. No-op (returns a zeroed result) when db is missing, maxBytes is not a positive finite number, or the cache already fits the budget.

LRU is approximated by the timestamp set at cache time (least recent = oldest), so the most recently downloaded tiles survive an over-budget pass.
Parameters
- db: IDBDatabase | null | undefined
  The open IndexedDB database (e.g. IndexedDB._db).
- maxBytes: number
  Byte budget for the persistent layer/tile cache.
Returns Promise<EvictionResult>
Eviction summary (counts + reclaimed/total bytes).
Example
```
const { evicted, freedBytes } = await evictToQuota(IndexedDB._db, 250 * 1024 * 1024);
```
- Defined in src/capabilities/offline/db/eviction.ts:150