The namer makes sure of the chunk month partition before its write

CI's fresh database had no release_chunks partition yet: the batch store
creates it on its own path, the namer's test wrote a chunk without it.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

app/services/pending_namer.ts

@@ -9,6 +9,7 @@ import { XoverClient } from '#lib/nntp/index'
 import { RangeIndexer, type ReleaseChunk } from '#lib/edge/index'
 import { identityKey } from '#lib/release/keys'
 import BatchStore from '#services/batch_store'
+import ChunkPartitions from '#services/chunk_partitions'
 import Corpus from '#services/corpus'
 import RuleSets from '#services/rule_sets'
 import { PENDING } from '#services/pending_ladder'
@@ -135,6 +136,8 @@ export class PendingNamer {
     const candidates = batch.candidates
       .filter((c) => c.releaseKey === found.key)
       .map((c) => ({ ...c, upload: found.upload }))
+    // The chunk's month partition, as the batch store makes sure of before its writes.
+    await ChunkPartitions.ensure()
     await db.transaction(async (trx) => {
       const blockId = await BatchStore.blockOf(trx, range)
       await BatchStore.writeReleases(