Implement Owner Panel features and maintenance mode handling

- Introduced the Owner Panel with new routes and UI components for managing guilds, user blacklists, feature flags, and bot presence.
- Added maintenance mode functionality to prevent non-owner users from executing commands during maintenance periods.
- Enhanced localization with new keys for Owner Panel features in both English and German.
- Updated job processing to include a presence refresh job, ensuring the bot's status is regularly updated.
- Improved environment configuration to support owner user IDs for access control.

apps/webui/src/app/api/owner/changelog/route.ts

@@ -0,0 +1,73 @@
+import { NextResponse } from 'next/server';
+import { ChangelogEntrySchema } from '@nexumi/shared';
+import { toApiErrorResponse } from '@/lib/auth';
+import { writeOwnerAudit } from '@/lib/owner-audit';
+import { requireOwner } from '@/lib/owner-auth';
+import { prisma } from '@/lib/prisma';
+
+export async function GET() {
+  try {
+    await requireOwner('VIEWER');
+    const entries = await prisma.changelogEntry.findMany({ orderBy: { publishedAt: 'desc' } });
+    return NextResponse.json({
+      entries: entries.map((entry) => ({
+        ...entry,
+        publishedAt: entry.publishedAt.toISOString(),
+        createdAt: entry.createdAt.toISOString(),
+        updatedAt: entry.updatedAt.toISOString()
+      }))
+    });
+  } catch (error) {
+    return toApiErrorResponse(error);
+  }
+}
+
+export async function POST(request: Request) {
+  try {
+    const session = await requireOwner('ADMIN');
+    const body = ChangelogEntrySchema.parse(await request.json());
+    const entry = await prisma.changelogEntry.create({
+      data: {
+        version: body.version,
+        title: body.title,
+        body: body.body,
+        publishedAt: body.publishedAt ? new Date(body.publishedAt) : undefined
+      }
+    });
+    await writeOwnerAudit(prisma, {
+      actorUserId: session.user.id,
+      action: 'changelog.create',
+      targetType: 'ChangelogEntry',
+      targetId: entry.id,
+      after: entry
+    });
+    return NextResponse.json(entry);
+  } catch (error) {
+    return toApiErrorResponse(error);
+  }
+}
+
+export async function DELETE(request: Request) {
+  try {
+    const session = await requireOwner('ADMIN');
+    const id = new URL(request.url).searchParams.get('id');
+    if (!id) {
+      return NextResponse.json({ error: 'id required' }, { status: 400 });
+    }
+    const before = await prisma.changelogEntry.findUnique({ where: { id } });
+    if (!before) {
+      return NextResponse.json({ error: 'Not found' }, { status: 404 });
+    }
+    await prisma.changelogEntry.delete({ where: { id } });
+    await writeOwnerAudit(prisma, {
+      actorUserId: session.user.id,
+      action: 'changelog.delete',
+      targetType: 'ChangelogEntry',
+      targetId: id,
+      before
+    });
+    return NextResponse.json({ ok: true });
+  } catch (error) {
+    return toApiErrorResponse(error);
+  }
+}