feat(welcome): add welcome page for new users after first login

Shows six feature cards and two next steps (Steam, import). The dashboard
redirects to it while Auth settings.welcomeSeenAt is null; "Let's go" and
"Skip" set the stamp. Settings links to it to reopen later.

public/i18n/de.json

@@ -51,6 +51,7 @@
     "ROLE": "Rolle",
     "CREATED_DATE": "Mitglied seit",
     "LAST_LOGIN": "Letzter Login",
+    "OPEN_WELCOME": "Willkommensseite erneut anzeigen",
     "DARK_THEME": "Dunkles Design",
     "LANGUAGE": "Sprache",
     "LANGUAGE_OPTIONS": {
@@ -635,6 +636,29 @@
     "LOAD_ERROR": "Die Neuigkeiten konnten nicht geladen werden.",
     "EMPTY": "Noch nichts Neues."
   },
+  "WELCOME": {
+    "TITLE": "Willkommen bei ToBePlayed",
+    "INTRO": "ToBePlayed sammelt deine Spiele an einem Ort: was du besitzt, was du spielst, was als Nächstes kommt.",
+    "FEATURE_LIBRARY": "Bibliothek und Pile of Shame",
+    "FEATURE_LIBRARY_TEXT": "Alle deine Spiele mit Spielzeit, Filtern und Suche. Der Pile zeigt, was du nie angefangen hast.",
+    "FEATURE_STATUS": "Status",
+    "FEATURE_STATUS_TEXT": "Markiere ein Spiel als spielend, durch, komplett oder abgebrochen, mit Bewertung und Notizen.",
+    "FEATURE_STATS": "Deine Statistiken",
+    "FEATURE_STATS_TEXT": "Summen, der Pile in Stunden, meistgespielte Spiele, Genres und durchgespielte Spiele pro Jahr.",
+    "FEATURE_PROFILE": "Öffentliches Profil",
+    "FEATURE_PROFILE_TEXT": "Teile deine Statistiken und was du spielst per Link. Aus, bis du es einschaltest.",
+    "FEATURE_IMPORT": "Import",
+    "FEATURE_IMPORT_TEXT": "Hole Spiele anderer Plattformen herein: Liste, CSV, Exporte oder ein Bookmarklet.",
+    "FEATURE_DASHBOARD": "Dein Dashboard",
+    "FEATURE_DASHBOARD_TEXT": "Ordne, verstecke und vergrößere die Kacheln. Es folgt dir aufs Handy.",
+    "OPEN": "Öffnen",
+    "NEXT_STEPS": "Nächste Schritte",
+    "STEP_STEAM": "Steam-Konto verknüpfen",
+    "STEP_IMPORT": "Deine Spiele importieren",
+    "DONE": "Erledigt",
+    "GO": "Los geht's",
+    "SKIP": "Überspringen"
+  },
   "ADMIN_NEWS": {
     "NEW": "Neuer Eintrag",
     "EDIT": "Eintrag bearbeiten",

public/i18n/en.json

@@ -51,6 +51,7 @@
     "ROLE": "Role",
     "CREATED_DATE": "Member since",
     "LAST_LOGIN": "Last login",
+    "OPEN_WELCOME": "Show the welcome page again",
     "DARK_THEME": "Dark theme",
     "LANGUAGE": "Language",
     "LANGUAGE_OPTIONS": {
@@ -635,6 +636,29 @@
     "LOAD_ERROR": "The news could not be loaded.",
     "EMPTY": "Nothing new yet."
   },
+  "WELCOME": {
+    "TITLE": "Welcome to ToBePlayed",
+    "INTRO": "ToBePlayed keeps your games in one place: what you own, what you play, what is next.",
+    "FEATURE_LIBRARY": "Library and Pile of Shame",
+    "FEATURE_LIBRARY_TEXT": "All your games with playtime, filters and search. The pile shows what you never started.",
+    "FEATURE_STATUS": "Statuses",
+    "FEATURE_STATUS_TEXT": "Mark a game as playing, finished, completed or dropped, with rating and notes.",
+    "FEATURE_STATS": "Your stats",
+    "FEATURE_STATS_TEXT": "Totals, the pile in hours, most played games, genres and finished games per year.",
+    "FEATURE_PROFILE": "Public profile",
+    "FEATURE_PROFILE_TEXT": "Share your stats and what you play with a link. Off until you switch it on.",
+    "FEATURE_IMPORT": "Import",
+    "FEATURE_IMPORT_TEXT": "Bring in games from other platforms: a list, a CSV, exports or a bookmarklet.",
+    "FEATURE_DASHBOARD": "Your dashboard",
+    "FEATURE_DASHBOARD_TEXT": "Order, hide and resize the tiles. It follows you to the phone.",
+    "OPEN": "Open",
+    "NEXT_STEPS": "Next steps",
+    "STEP_STEAM": "Link your Steam account",
+    "STEP_IMPORT": "Import your games",
+    "DONE": "Done",
+    "GO": "Let's go",
+    "SKIP": "Skip"
+  },
   "ADMIN_NEWS": {
     "NEW": "New entry",
     "EDIT": "Edit entry",