chore(8.0): final pre-RC1 sweep — API consistency, named errors, orphans, zero-cast codebase

src/storage/adapters/fileSystemStorage.ts

@@ -1612,6 +1612,8 @@ export class FileSystemStorage extends BaseStorage {
       } else {
         const stale = await this.isWriterLockStale(existing)
         if (!stale) {
+          // Consumer-facing error contract: callers detect this case via
+          // err.code and read the holder's details from err.lockInfo.
           const err = new Error(
             `Another writer holds this Brainy directory.\n` +
             `  PID:        ${existing.pid} on host ${existing.hostname}\n` +
@@ -1622,9 +1624,9 @@ export class FileSystemStorage extends BaseStorage {
             `For diagnostic queries against this live store, use:\n` +
             `  const reader = await Brainy.openReadOnly({ storage: { type: 'filesystem', rootDirectory: '${this.rootDir}' } })\n\n` +
             `If you have verified the existing lock is stale (e.g. a crashed writer on a different host that PID liveness cannot reach), pass { force: true }.`
-          )
-          ;(err as any).code = 'BRAINY_WRITER_LOCKED'
-          ;(err as any).lockInfo = existing
+          ) as Error & { code: string; lockInfo: WriterLockInfo }
+          err.code = 'BRAINY_WRITER_LOCKED'
+          err.lockInfo = existing
           throw err
         }
         console.warn(