feat(admin): DB CRUD panel + /api/admin endpoints (#38)

- ADMIN button in the mission-control header opens a table picker + row grid with add/edit/delete (components/admin-panel.tsx), deliberately unauthenticated by explicit request
- /api/admin/tables and /api/admin/tables/{name}/rows driven off a name→table registry built from lib/db/schema.ts (lib/db/admin.ts) — no per-table code; 404 unknown table, 400 malformed payload, 409 constraint violation
- OpenAPI spec updated for all four admin operations + Admin* schemas
- unit: lib/db/admin.test.ts (registry, CRUD round-trips, composite PKs, error mapping); e2e: read-only admin.spec.ts

components/mission-control.tsx

@@ -1,7 +1,9 @@
 'use client'
 
 import { useCallback, useEffect, useState } from 'react'
+import { AdminPanel } from '@/components/admin-panel'
 import { Badge } from '@/components/ui/badge'
+import { Button } from '@/components/ui/button'
 import { Panel, PanelContent, PanelHeader, PanelTitle } from '@/components/ui/panel'
 import { Progress } from '@/components/ui/progress'
 import { StatCard } from '@/components/ui/stat-card'
@@ -57,6 +59,8 @@ export function MissionControl() {
   // #27 — the active tab survives a page refresh. Restored from localStorage on mount; null until
   // then so SSR and the first client render agree on the default tab (no hydration mismatch).
   const [activeTab, setActiveTab] = useState<string | null>(null)
+  // #38 — admin DB CRUD overlay, opened from the header.
+  const [adminOpen, setAdminOpen] = useState(false)
 
   useEffect(() => {
     let cancelled = false
@@ -210,6 +214,9 @@ export function MissionControl() {
 
         <Badge variant="SCANNING">SECTOR SCAN</Badge>
 
+        {/* #38 — admin DB CRUD, no auth by design (see components/admin-panel.tsx) */}
+        <Button size="SM" onClick={() => setAdminOpen(true)}>ADMIN</Button>
+
         <span
           style={{
             color: 'var(--color-green)',
@@ -225,6 +232,8 @@ export function MissionControl() {
         </span>
       </header>
 
+      {adminOpen && <AdminPanel onClose={() => setAdminOpen(false)} />}
+
       {/* ── BODY ── */}
       <div
         style={{