watchdogd v4.1

Changes

• Add watchdogctl list-clients command to display currently subscribed
  clients to the process supervisor. Outputs to stdout in either table
  format (default) with colored headers, or JSON format with -j/--json
• New global -j, --json option for machine-readable output, currently
  supported by list-clients and status commands
• New API: wdog_clients() returns array of wdog_client_t structs for
  programmatic access to subscribed clients. See API documentation at
  https://codedocs.xyz/troglobit/watchdogd/wdog_8h.html
• Enhance watchdogctl status command to display formatted output by
  default, with device information, capabilities, and reset history in
  a human-readable table format. Use -j/--json for JSON output

Fixes

• Fix #48: generic scripts running more than 1 second would fail with
  false "critical error" reports and cause unwanted system reboots due
  to uninitialized exit status variable. Found and fixed by Fiona Klute
• Fix #55: watchdogctl reload with tempmon crashes watchdogd
• Fix #56: issue causing unwanted reboot when watchdogctl reload was
  called while a generic monitor script was running. The script_watcher
  timer was not stopped during reload, leading to an invalid PID (-1)
  being used, which triggered a system reset
• Fix memory leak in generic monitor with optional script path, would
  be triggered on watchdogctl reload