Drop garbage uploads early (D42)

Random-named uploads that never get a real name or password were ~90% of
what seeding stores. Two filters:

- before storing (seeding, ingest): random-named uploads of a dropped
  signature (posting tool from the Message-ID, first group) or of a
  release dropped after its probe aren't stored; 2% of a dropped
  signature's releases are still kept and probed. Stored files of dropped
  signatures aren't probed.
- after a probe: a random-named release that is still unnamed, without
  password, names from files or spot, with all its probes done, and
  encrypted, a container or missing its first article, is deleted and
  tombstoned in dropped_releases.

Signatures are learned by gc:scheduler from a sample of probed releases
(signature_probes); garbage:learn --seed fills it from existing files.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

app/services/IngestService.ts

@@ -4,6 +4,7 @@ import type { QueryClientContract } from '@adonisjs/lucid/types/database'
 import type { Knex } from 'knex'
 import QueueService from '#services/QueueService'
 import NameService from '#services/NameService'
+import GarbageFilter from '#services/GarbageFilter'
 import type { IngestSegment } from '#lib/ingest/segment'
 
 // Header parsing is pure and lives in lib, so seeding nodes need no database (CONCEPT.md D37).
@@ -110,7 +111,14 @@ function validDate(date?: Date) {
  * no-op. See CONCEPT.md (D12).
  */
 class IngestService {
-  async ingest(segments: IngestSegment[]): Promise<CompletedBinary[]> {
+  async ingest(batch: IngestSegment[]): Promise<CompletedBinary[]> {
+    // Garbage isn't stored at all: no release, binary or parts (CONCEPT.md D42).
+    const { kept: segments } = await GarbageFilter.keep(batch, (s) => ({
+      name: s.name,
+      messageId: s.messageId,
+      groups: s.groups,
+      releaseKey: s.release?.key ?? s.fileKey,
+    }))
     if (segments.length === 0) return []
 
     // Short statements, no enclosing transaction: every step is idempotent, and