Scoped API tokens for the random endpoint, with a management page

Backend: a GreetingToken model stores only a SHA-256 hash of a j621r_…
key (shown once at creation) plus label, prefix, created/last-used. A
dedicated GreetingTokenAuthentication understands the usual
'Authorization: Token …' header but is registered only on RandomItemView
(alongside the normal token auth), so a greeting token authenticates
/api/random/ and is rejected with 401 everywhere else — exactly the scope
shell greetings need. Endpoints: GET/POST /api/auth/greeting-tokens/ and
DELETE /api/auth/greeting-tokens/{id}/ (own tokens only; the list never
returns keys or hashes).

Frontend: /tokens page (Account → Shell tokens card, command palette entry)
lists tokens with label, prefix, created/last-used and revoke (shared
confirm dialog). Creating one shows the key with Copy and 'Copy for fish'
buttons plus a pointer to extras/fish_greeting.

Tests: apps/accounts/tests/test_greeting_tokens.py — 9 tests covering
create-once semantics and hashing, hidden keys in listings, the scope
guarantee (random 200 with a signed URL; 401 on files, storage, me, tags
cloud, delete and the token list itself), unknown/revoked keys, cross-user
revocation, last-used tracking and label limits.

Verified live: created a token, rolled /random (signed URL), got 401 from
four other endpoints, saw the list omit secrets, revoked it (204) and the
same key then 401'd on /random. Full suite: 39 tests green.

backend/apps/accounts/migrations/0007_greetingtoken.py

@@ -0,0 +1,30 @@
+# Generated by Django 6.1.1 on 2026-09-18 18:25
+
+import django.db.models.deletion
+from django.conf import settings
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('accounts', '0006_encrypt_e621_api_keys'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='GreetingToken',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('key_hash', models.CharField(max_length=64, unique=True)),
+                ('prefix', models.CharField(max_length=16)),
+                ('label', models.CharField(blank=True, default='', max_length=100)),
+                ('created_at', models.DateTimeField(auto_now_add=True)),
+                ('last_used_at', models.DateTimeField(blank=True, null=True)),
+                ('user', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='greeting_tokens', to=settings.AUTH_USER_MODEL)),
+            ],
+            options={
+                'ordering': ['-created_at'],
+            },
+        ),
+    ]