Add OmaRecord with optional keystroke overlay

[inde3d100]

Summary

• brand screen recording as OmaRecord, with a standalone omarecord command and matching menu and hotkey labels
• add --show-keystrokes using Show Me The Key
• keep overlay ownership scoped by PID/start time and clean it on stop, startup failure, signals, or unexpected recorder exit
• reject portal capture where a separate overlay cannot be guaranteed in the recording
• add Hyprland placement rules, focused shell coverage, and manual instructions

Verification

• bash test/shell.d/screenrecording-test.sh
• bash test/shell.d/menu-test.sh
• bin/omarchy commands --check (454 commands)
• syntax-checked all 457 bin/omarchy-* commands
• ./test/all completed with six failures outside the changed files: bin-style-test.sh, config-test.sh, launch-about-test.sh, monitor-recovery-test.sh, theme-install-guards-test.sh, and unowned-system-paths-test.sh