fix: add missing translations and fix type error

Added missing translation keys in all language dictionaries:
- "Slot" (en: "Slot", fr: "Créneau", de: "Zeitfenster")
- "© 2024 Playchoo Manager. Venue administration portal." (translated to fr and de)

Fixed type error in ClubProfileTab.tsx:
- hasFieldValue() now explicitly returns boolean using Boolean() wrapper

This resolves all TypeScript compilation errors.

dictionaries/de.json

@@ -834,5 +834,7 @@
   "swap request": "Tauschanfrage",
   "Waiting for": "Warten auf",
   "approval(s)": "Genehmigung(en)",
-  "All approved": "Alle genehmigt"
+  "All approved": "Alle genehmigt",
+  "Slot": "Zeitfenster",
+  "© 2024 Playchoo Manager. Venue administration portal.": "© 2024 Playchoo Manager. Verwaltungsportal für Veranstaltungsorte."
 }

dictionaries/en.json

@@ -866,5 +866,7 @@
   "Checking authentication...": "Checking authentication...",
   "Redirecting to login...": "Redirecting to login...",
   "Please log in to access the venue management portal.": "Please log in to access the venue management portal.",
-  "If you are a venue administrator and do not have access, please contact support.": "If you are a venue administrator and do not have access, please contact support."
+  "If you are a venue administrator and do not have access, please contact support.": "If you are a venue administrator and do not have access, please contact support.",
+  "Slot": "Slot",
+  "© 2024 Playchoo Manager. Venue administration portal.": "© 2024 Playchoo Manager. Venue administration portal."
 }

dictionaries/fr.json

@@ -830,5 +830,7 @@
   "swap request": "demande d'échange",
   "Waiting for": "En attente de",
   "approval(s)": "approbation(s)",
-  "All approved": "Toutes approuvées"
+  "All approved": "Toutes approuvées",
+  "Slot": "Créneau",
+  "© 2024 Playchoo Manager. Venue administration portal.": "© 2024 Playchoo Manager. Portail d'administration de lieu."
 }

src/app/[locale]/admin/clubs/[club_id]/tabs/ClubProfileTab.tsx

@@ -251,7 +251,7 @@ export default function ClubProfileTab({ clubId, onUpdate }: ClubProfileTabProps
   }
 
   function hasFieldValue(value: string): boolean {
-    return value && value.trim().length > 0;
+    return Boolean(value && value.trim().length > 0);
   }
 
   // Loading state