fix(metadata-protocol): a lone prose key or none on an unlocked item is refused as adding lock keys, not setting a lock

Claude-Session: https://claude.ai/code/session_01ADzJtzYTLUfgrRZHxkagkX
Co-authored-by: Claude <noreply@anthropic.com>

Author: claude

packages/metadata-protocol/src/protocol.save-door-lock-family.test.ts

@@ -227,7 +227,8 @@ for (const writeFace of AUTHOR_FACES) {
             await protocol.saveMetaItem({ type: 'app', name, item: app(name), writeFace });
             for (const family of [{ _lock: 'full' }, { _lock: 'no-overlay' }, { _lock: 'no-delete' }, { _lock: 'none' }, { _lockReason: 'why' }]) {
                 const err = await refusalOf(() => protocol.saveMetaItem({ type: 'app', name, item: app(name, family), writeFace }));
-                expectLockFamilyRefusal(err, Object.keys(family), 'set a lock on it');
+                // A lone prose key, or `none`, binds nothing: it adds keys, not a lock.
+                expectLockFamilyRefusal(err, Object.keys(family), family._lock && family._lock !== 'none' ? 'set a lock on it' : 'add lock keys to it');
             }
             expect(storedFamily('app', name)).toEqual({});
         });

packages/metadata-protocol/src/protocol.ts

@@ -1103,7 +1103,7 @@ function authoredLockFamilyRefusal(
     const servedLock = served._lock ?? 'none';
     const sentLock = sent._lock ?? 'none';
     const effect = servedLock === 'none'
-        ? 'set a lock on it'
+        ? (sentLock === 'none' ? 'add lock keys to it' : 'set a lock on it')
         : sentLock === 'none' ? 'remove its lock' : 'change its lock';
     const err = new Error(
         `Remove ${keys.map((key) => `\`${key}\``).join(', ')} from ${type} '${saveName}' and send it again. `