feat(PROJ-44): Snippet + Quellen-Badge in Such-Trefferliste

- Zweite Zeile unter dem Betreff zeigt Manticore-Snippet
  mit <b>-Highlights, gerendert via dangerouslySetInnerHTML
  ueber sanitizeSnippet
- Quellen-Badge je match_field (Subject, Body, PDF-Anhang,
  Dateiname, Absender, Empfaenger) als kleines Tailwind-Pill
- Nur sichtbar wenn das Backend ein snippet zurueckliefert

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/app/search/page.tsx

@@ -3,7 +3,8 @@
 import { useState, useCallback, useEffect, useRef } from "react";
 import { useRouter } from "next/navigation";
 import { useAuth } from "@/hooks/useAuth";
-import { searchEmails, exportMailsZIP, exportEDiscovery, uploadMailFilesUser, getUploadProgressUser, listSavedSearches, createSavedSearch, deleteSavedSearch, type SearchHit, type UploadJob, type SavedSearch } from "@/lib/api";
+import { searchEmails, exportMailsZIP, exportEDiscovery, uploadMailFilesUser, getUploadProgressUser, listSavedSearches, createSavedSearch, deleteSavedSearch, type SearchHit, type SearchMatchField, type UploadJob, type SavedSearch } from "@/lib/api";
+import { sanitizeSnippet } from "@/lib/sanitize";
 import { Navbar } from "@/components/navbar";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
@@ -51,6 +52,36 @@ function formatBytes(bytes: number): string {
   return `${(bytes / (1024 * 1024)).toFixed(1)} MB`;
 }
 
+const MATCH_FIELD_LABEL: Record<SearchMatchField, string> = {
+  subject: "📨 Subject",
+  body: "✉️ Body",
+  attachment_text: "📄 PDF-Anhang",
+  attachment_names: "📎 Dateiname",
+  from_addr: "👤 Absender",
+  to_addr: "📧 Empfänger",
+};
+
+function MatchSourceBadge({ field }: { field: SearchMatchField }) {
+  return (
+    <span className="inline-flex items-center rounded-full bg-muted px-2 py-0.5 text-[10px] font-medium text-muted-foreground whitespace-nowrap">
+      {MATCH_FIELD_LABEL[field]}
+    </span>
+  );
+}
+
+function SnippetLine({ hit }: { hit: SearchHit }) {
+  if (!hit.snippet) return null;
+  return (
+    <div className="mt-1 flex items-start gap-2 text-xs text-muted-foreground font-normal">
+      {hit.match_field && <MatchSourceBadge field={hit.match_field} />}
+      <span
+        className="min-w-0 flex-1 truncate [&_b]:font-semibold [&_b]:text-foreground"
+        dangerouslySetInnerHTML={{ __html: sanitizeSnippet(hit.snippet) }}
+      />
+    </div>
+  );
+}
+
 export default function SearchPage() {
   const { user, loading: authLoading } = useAuth();
   const router = useRouter();
@@ -621,12 +652,15 @@ export default function SearchPage() {
                         </TableCell>
                         <TableCell className="max-w-[14rem] truncate text-sm">{hit.from || "-"}</TableCell>
                         <TableCell className="font-medium">
-                          <span>{hit.subject || "(kein Betreff)"}</span>
+                          <div className="flex items-center gap-2">
+                            <span className="truncate">{hit.subject || "(kein Betreff)"}</span>
                             {hit.thread_size && hit.thread_size > 1 && (
-                            <span className="ml-2 inline-flex items-center rounded-full bg-muted px-1.5 py-0.5 text-xs text-muted-foreground font-normal">
+                              <span className="inline-flex items-center rounded-full bg-muted px-1.5 py-0.5 text-xs text-muted-foreground font-normal">
                                 {hit.thread_size}
                               </span>
                             )}
+                          </div>
+                          <SnippetLine hit={hit} />
                         </TableCell>
                         <TableCell className="max-w-[12rem] truncate text-sm text-muted-foreground">{hit.to || "-"}</TableCell>
                         <TableCell className="text-center text-sm">