[bug]: Reject invalid page values in artifact, project, and registry list commands

[PrasunaEnumarthy]

Description

Some paginated list commands validate --page-size but do not validate --page.

Steps to Reproduce

1. Run command:
   • harbor artifact list --page 0
   • harbor project list --page -1
   • harbor registry list --page 0
2. Observe that the command does not fail early with a clear validation error.

Expected Behavior

Commands that support pagination should reject invalid page values before making API calls.

Actual Behavior

Some commands validate --page-size but not --page, so invalid page values are accepted and passed to the API.

Environment

• OS: any
• Tool version: current main branch
• Other relevant details: none

Additional Context

Reference implementation:

• cmd/harbor/root/project/logs.go

Target files:

• cmd/harbor/root/artifact/list.go
• cmd/harbor/root/project/list.go
• cmd/harbor/root/registry/list.go

This is a follow-up to the validation added for --page-size in #631.