refactor: hardcode non-secret Discord IDs as constants

Move guild ID, apotheosis role ID, Discord client ID, and redirect URI
from env vars to hardcoded constants — none of these are secrets, and
hardcoding removes unnecessary runtime configuration surface. Update
tests to use the real IDs and drop now-irrelevant env var scenarios.

apps/web/src/context/gameContext.tsx

@@ -737,7 +737,7 @@ export const GameProvider = ({
       setSchemaOutdated(data.schemaOutdated);
       setSaveSchemaVersion(data.state.schemaVersion ?? 0);
       setCurrentSchemaVersion(data.currentSchemaVersion);
-      setInGuild(data.inGuild === true);
+      setInGuild(data.inGuild);
 
       // Fetch number format preference from profile (fire-and-forget, non-blocking)
       void fetch(`/api/profile/${data.state.player.discordId}`).