X_CONFIG_KEY_UNREAD
Means
AppConfig declares a key nothing in packages/*/src reads
Typical cause
the shape three deleted fields had — pwa.installPrompt, auth.afterSignInPath, ai.modelEnv were each declared, defaulted, merged and read by nobody, so setting them did nothing and said nothing. A ratchet, because a key may be legitimately app-facing; a pin carries the sentence naming its reader, never a boolean
Fix
delete the key from config.ts and defaults(), or wire it, or pin it with the sentence that names its reader