Audit CLI commands for consistent --json output support

Several CLI commands output lists/tables but don't support --json for machine-readable output. We should audit and standardize this.

Pattern

Commands that output lists should use:

• FormatOptions embedded struct (provides --json flag)
• opts.IsJSON() check with structured output via PrintJSON()

Current gaps

Commands using ui.NewTable but missing JSON support:

• app_history.go
• debug_lsvd.go
• debug_netdb.go
• doctor_config.go

Tasks

• Add JSON output to app_history.go (user-facing command)
• Evaluate if debug/doctor commands need JSON (probably low priority)
• Add CLAUDE.md guidance for this pattern so new commands follow it