feat: Regeln (Betrag/Transfer/Konto-Texte) + Münz-Icon + pastellgrünes Theme

Regeln:
- Schlagwörter mit optionaler Betragsbedingung (z. B. „SV = 5.00 → Restaurant");
  Betrags-Regeln gewinnen vor betragslosen
- Transfer-Schlagwörter (Text → Transfer) auf der Konten-Seite
- Konto-Identifikator-Art „Text": erkennt das Zielkonto eines Transfers aus dem
  Buchungstext (längster passender Text gewinnt)
- Migration 0007, Endpunkte, Tests (Betrag/Transfer/Konflikt), gesamt 30 grün

Optik:
- App-Icon: Münzhaufen (aus Nutzer-SVG) weiß auf grünem Grund, klein gehalten
- Farbschema auf pastelliges Grün (Akzent hell/dunkel + Favicon)

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

web/src/locales/en.json

@@ -128,6 +128,7 @@
     "openingDate": "As of",
     "identifiers": "Identifiers (IBAN etc.)",
     "addIdentifier": "Add identifier",
+    "textIdentPlaceholder": "e.g. Savings, Deposit",
     "identShort": "id(s)",
     "total": "Total",
     "empty": "No accounts yet. Create your first account.",
@@ -144,7 +145,14 @@
   "identifierKinds": {
     "iban": "IBAN",
     "account_no": "Account number",
-    "card_no": "Card number"
+    "card_no": "Card number",
+    "text": "Text (detection)"
+  },
+  "transferRules": {
+    "title": "Transfer detection",
+    "hint": "Transactions whose text contains one of these words are recognized as a transfer. The target account is guessed from the booking text via each account's detection texts (edit account, kind Text).",
+    "wordPlaceholder": "Word (e.g. Transfer)",
+    "empty": "No transfer keywords yet."
   },
   "categories": {
     "title": "Categories",
@@ -163,6 +171,7 @@
     "keywordsTitle": "Keywords – {{name}}",
     "keywordsHint": "Transactions whose payee or description contains one of these words are automatically assigned to this category on future imports.",
     "keywordAdd": "Type a word and press Enter",
+    "keywordAmount": "Amount (optional)",
     "keywordEmpty": "No keywords yet.",
     "keywordEditHint": "Double-click a keyword to edit it.",
     "searchPlaceholder": "Search category …"