Refactor: DashboardView in Karten zerlegen (Phase 4a)

DashboardView 849 -> ~40 Zeilen Orchestrator. Sechs eigenständige Karten unter
components/dashboard/, jede mit eigenem Daten-Hook (react-query, geteilte Keys):
- RadialGauge, SystemStatusCard (useSystemStatus)
- UpdatesCard (useUpdates+useJobs; OS/Engine-Update, Reboot, Modell-Upgrade,
  Sudo-Modal, invalidiert nach Aktionen)
- AgentStatusCard (useAgentStatus+useModels; Gehirn-Wechsel-Modal)
- RolesCard (useModels), MemoryInputCard (useMemory), TokenStatsCard (useTokenStats)

Kein manuelles useEffect+setInterval mehr; useDialog statt lokalem Dialog-State.
Verifiziert: tsc grün, Build grün, alle 6 Karten rendern, Live-Daten + Pricing-
Footer korrekt, keine Konsolenfehler.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/components/dashboard/MemoryInputCard.tsx

@@ -0,0 +1,92 @@
+import { useState } from "react"
+import { Brain, Plus } from "lucide-react"
+import { api } from "@/lib/api"
+import { useMemory, useQueryClient } from "@/lib/queries"
+
+export function MemoryInputCard() {
+  const qc = useQueryClient()
+  const { data: memories = [] } = useMemory({ limit: 3 })
+  const [memContent, setMemContent] = useState("")
+  const [memCat, setMemCat] = useState("stable")
+  const [savingMem, setSavingMem] = useState(false)
+
+  async function saveQuickMemory() {
+    if (!memContent.trim() || savingMem) return
+    setSavingMem(true)
+    try {
+      await api("/api/memory", {
+        method: "POST",
+        body: JSON.stringify({ content: memContent, category: memCat, source: "dashboard" }),
+      })
+      setMemContent("")
+      qc.invalidateQueries({ queryKey: ["memory"] })
+    } catch (e) {
+      console.error(e)
+    } finally {
+      setSavingMem(false)
+    }
+  }
+
+  return (
+    <div className="rounded-2xl border border-border/60 bg-card/45 backdrop-blur-md p-5 shadow-lg shadow-black/15 flex flex-col justify-between">
+      <div>
+        <div className="flex items-center gap-2 mb-4">
+          <Brain className="h-4.5 w-4.5 text-primary" />
+          <h2 className="text-sm font-semibold tracking-wide uppercase text-foreground">Gedächtnis</h2>
+        </div>
+
+        <div className="space-y-3">
+          <textarea
+            value={memContent}
+            onChange={(e) => setMemContent(e.target.value)}
+            placeholder="Fakt / Regel im Pool speichern..."
+            rows={2}
+            className="w-full resize-none rounded-xl border border-border/50 bg-background/30 p-2 text-[10px] outline-none focus:ring-1 focus:ring-primary transition-all leading-normal"
+          />
+          <div className="flex items-center gap-2 justify-between">
+            <select
+              value={memCat}
+              onChange={(e) => setMemCat(e.target.value)}
+              className="h-7 rounded-lg border border-border/50 bg-background/50 px-2 text-[10px] outline-none cursor-pointer"
+            >
+              <option value="stable">🔵 Fakt</option>
+              <option value="instruction">📋 Regel</option>
+              <option value="user">👤 User</option>
+              <option value="versioned">🟡 Version</option>
+            </select>
+            <button
+              onClick={saveQuickMemory}
+              disabled={!memContent.trim() || savingMem}
+              className="flex h-7 items-center gap-1 rounded-lg bg-primary px-3 text-[10px] font-semibold text-primary-foreground hover:opacity-90 disabled:opacity-50 transition-all cursor-pointer"
+            >
+              <Plus className="h-3.5 w-3.5" /> Speichern
+            </button>
+          </div>
+        </div>
+
+        <div className="mt-3.5 space-y-1.5">
+          <div className="text-[9px] text-muted-foreground uppercase font-bold tracking-wider">Zuletzt gespeichert:</div>
+          <div className="max-h-20 overflow-y-auto space-y-1 pr-1 scrollbar-thin">
+            {memories.length === 0 ? (
+              <div className="text-[10px] text-muted-foreground/75 py-1">Keine Einträge vorhanden.</div>
+            ) : (
+              memories.map((m) => (
+                <div key={m.id} className="text-[10px] bg-background/10 border border-border/30 rounded p-1.5 flex items-start gap-1.5">
+                  <span className="shrink-0 text-[8px] font-mono text-muted-foreground/80 px-1 py-0.5 rounded bg-muted/20">
+                    {m.category}
+                  </span>
+                  <span className="truncate flex-1 text-muted-foreground hover:text-foreground transition-colors" title={m.content}>
+                    {m.content}
+                  </span>
+                </div>
+              ))
+            )}
+          </div>
+        </div>
+      </div>
+      <div className="mt-4 text-[10px] text-muted-foreground/80 border-t border-border/30 pt-3">
+        Steht allen Clients per MCP zur Verfügung.
+      </div>
+    </div>
+  )
+}