feat: default locale Russian, geo determines language for other countries

- localization-svc: defaultLocale ru, resolveLocale only by geo
- web-svc: DEFAULT_LOCALE ru, layout lang=ru, embeddedTranslations fallback ru
- countryToLocale: default ru when no country or unknown country

Co-authored-by: Cursor <cursoragent@cursor.com>

services/library-svc/drizzle/0001_thread_messages.sql

@@ -0,0 +1,13 @@
+CREATE TABLE IF NOT EXISTS library_thread_messages (
+  id SERIAL PRIMARY KEY,
+  thread_id TEXT NOT NULL REFERENCES library_threads(id) ON DELETE CASCADE,
+  message_id TEXT NOT NULL,
+  backend_id TEXT NOT NULL DEFAULT '',
+  query TEXT NOT NULL,
+  created_at TIMESTAMP DEFAULT NOW() NOT NULL,
+  response_blocks JSONB DEFAULT '[]',
+  status TEXT DEFAULT 'answering'
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS idx_thread_messages_thread_message
+  ON library_thread_messages(thread_id, message_id);