Deprecate `partio reset` in favor of `partio rewind`

[jcleira]

Summary

partio reset is a destructive command that wipes the entire checkpoint branch. partio rewind is the safer, more capable alternative. Mark reset as deprecated so users are redirected to rewind.

Source

entireio/cli changelog 0.5.3: "Deprecated entire reset command in favor of entire rewind"

Proposed Change

Mark partio reset as deprecated in Cobra:

• Hidden from partio --help output
• Prints a deprecation warning to stderr when invoked: Warning: 'partio reset' is deprecated and will be removed in a future release. Use 'partio rewind' instead.
• Command still executes so existing scripts are not broken during transition

Why This Matters

reset deletes all checkpoint history without recovery. Users who run it by mistake lose all captured session data. Deprecating it now sets expectations before eventual removal, and redirects users to the safer rewind command.