feat: Implement message handling commands for agent tool

- Added functionality for listing, reading, and searching messages in the ROM.
- Introduced new commands: `message-list`, `message-read`, and `message-search` with appropriate parameters and descriptions.
- Enhanced the CLI to support these commands, including JSON and text output formats.
- Updated system prompts and function schemas to reflect the new message handling capabilities.

src/cli/z3ed.cmake

@@ -59,6 +59,7 @@ add_executable(
   cli/handlers/sprite.cc
   cli/handlers/project.cc
   cli/handlers/command_palette.cc
+  cli/handlers/message.cc
   cli/handlers/agent.cc
   cli/handlers/agent/common.cc
   cli/handlers/agent/general_commands.cc