refactor(cli): restructure CLI to cmd/cli/app pattern and consolidate lifecycle commands

[t0mmylam]

Summary

Restructures the Skyhook CLI to follow the Kueue-style cmd/cli/app/ pattern and consolidates duplicate lifecycle commands into a single file with shared implementation.

Changes

Structure Refactor

• Move CLI commands from internal/cli/ to cmd/cli/app/
• Follows established patterns from kubectl plugins (Kueue)
• Keeps main.go minimal with command construction in app/ package

Code Consolidation

• Consolidate pause.go, resume.go, disable.go, enable.go → lifecycle.go
• Shared newLifecycleCmd() helper with config-driven behavior
• Refactor tests to use table-driven approach (lifecycle_test.go)

Linter Fixes

• Fix line length violation in package_rerun.go (212 → multi-line function signature)
• Eliminate duplicate code warnings via consolidation and //nolint:dupl where appropriate