Separate generic command protocol framing from Base record schemas

[codeforester]

Summary

base_cli.command_protocol still bundles Base's built-in record schemas and the BASE_COMMAND_PROTOCOL_V1 compatibility surface with the generic framing and schema registry.

Scope

• keep generic record framing, field validation, and schema registration in base_cli
• move Base-specific record names and schemas into Base's consumer adapter
• preserve the Bash peer protocol through an explicit consumer-owned registration/compatibility layer
• add tests proving a standalone consumer can use the protocol without Base record names or product assumptions

This follows base-cli#23 and is part of the remaining work tracked by #19.

Acceptance criteria

• importing and using generic command protocol code does not expose Base product schemas
• Base registers the schemas it needs at its integration boundary
• existing Base protocol behavior remains covered by Base tests