gui_toolkit 0.99.0

Added

• update (package tk_update): signed updates of a program, from Wren and opencode native. A Product (name, signing context, public key) checks what a release publishes: one manifest per platform and channel (manifest_name, channels optional), signed with Ed25519, for a strictly newer version and the release's own file name (check_release). place puts the downloaded program in place of the running one after its size and SHA-256 (Windows: renamed aside, put back on failure; Linux: renamed over), remove_leftovers cleans up at the next start, and manifest_of, manifest_bytes and sign are the release tool's side. docs/update.md.
• platform.set_app_id: the program's id on the Linux desktop, the name of its .desktop file: Wayland's app_id and X11's WM_CLASS (which windows on X11 had none of). By default the executable's file name, where every window said "gui_toolkit", so a task bar could not find the program's icon and name.

Changed

• tk release publishes a version on Windows or Linux (tools/tk), in place of tools/release.ps1, which is gone: the CHANGELOG section and the version, the commit, the annotated tag, the push and the GitHub release. The About picture is taken again on Windows only.

Fixed

• System fonts on Linux take fontconfig's aliases and generic families: font.load_system and font.has_system_family give "Courier New" the installed font the configuration binds to it (Liberation Mono, by 30-metric-aliases.conf), and monospace, serif, sans-serif and the other generic families the font fontconfig picks. They refused any answer whose family was not the one asked for, so such a name was missing and text fell to the next font.