refactor: rename zitare -> quotes (Zitate)

Zitare was opaque Latin/Italian-flavored branding. Renamed to clear
English "quotes" (DE: Zitate) matching short-concrete-noun cluster.

- Module, routes, API, i18n, standalone landing app, plans dirs
- Dexie tables: quotesFavorites, quotesLists, quotesListTags,
  customQuotes (dropped redundant "quotes" prefix on the last)
- Logo QuotesLogo, theme quotes.css, search provider, dashboard
  widget QuoteWidget
- German user-facing label "Zitate" (English brand stays Quotes)

Pre-launch, no data migration needed.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docs/MICROSERVICES_API_OVERVIEW.md

@@ -153,7 +153,7 @@ Diese Services sind für Matrix/Telegram konzipiert, nicht als direkte APIs:
 | matrix-todo-bot | 3314 | Task Management |
 | matrix-calendar-bot | 3315 | Kalender/Events |
 | matrix-food-bot | 3316 | Ernährungs-Tracking |
-| matrix-zitare-bot | 3317 | Zitate |
+| matrix-quotes-bot | 3317 | Zitate |
 | matrix-clock-bot | 3318 | Timer/Alarme |
 | matrix-tts-bot | 3023 | Sprachausgabe |
 
@@ -462,5 +462,5 @@ services/
 | 3314 | matrix-todo-bot | Bot |
 | 3315 | matrix-calendar-bot | Bot |
 | 3316 | matrix-food-bot | Bot |
-| 3317 | matrix-zitare-bot | Bot |
+| 3317 | matrix-quotes-bot | Bot |
 | 3318 | matrix-clock-bot | Bot |