PHLEGM v6 macros

Root: cfg/macros/
Suffix: *.macro.phlegm

Recursive folders, ZIP archives, and nested ZIP archives are supported. Archive layers use :: in source identities. Macro Config supports create/edit/save/rename/delete/execute plus Clone Commands softmode and New Archive. Every macro command executes through the normal PHLEGM parser and permission system. tree.lib owns hierarchy/container mechanics; macro.lib owns macro lifecycle/sequencing.

## r28: PNG screenshots

`SCREENSHOT [display-index] [file]`, GUI screenshot commands and timed macros
write actual PNG files. Default names end in `.png`. Explicit legacy `.bmp`
filenames are normalized to `.png` to avoid misleading BMP extensions.
PNG uses self-contained lossless RGB encoding (stored DEFLATE blocks),
without optional external codec libraries; existing BMP files are not deleted.
