feat(packaging): nix web console + plugin/script runner everywhere; fix tray zbus/tokio crash

Ship the management web console and the plugin/script runner across the packaging
matrix, and fix a Linux tray startup crash.

- nix: add punktfunk-web (Nitro SSR on bun) and punktfunk-scripting (Effect runner),
  with services.punktfunk.{web,scripting} modules. Both bun node_modules come from
  fixed-output derivations pinned to real deps hashes; patchShebangs the web
  node_modules so orval/paraglide/vite run in the sandbox. Validated on x86_64-linux
  (nix build .#punktfunk-{web,scripting,tray,host} all green).

- punktfunk-scripting now ships for deb/rpm/arch/nix/windows, mirroring the web-console
  mechanics (vendored bun on deb/rpm/arch, pkgs.bun on nix; one self-contained
  `bun build --target=bun` bundle). Opt-in: host Recommends it, but the systemd --user
  unit ships un-started (Windows registers its scheduled task disabled).

- fix(tray): build punktfunk-tray in its OWN cargo invocation on nix/rpm/arch. Cargo
  unifies features across one `cargo build`, so co-building the tray with the host pulls
  the host's ashpd->zbus/tokio onto the tray's shared zbus and it panics at startup
  ("there is no reactor running, must be called from the context of a Tokio 1.x
  runtime"). Isolated, the tray's zbus stays on async-io. The .deb already did this;
  runtime-verified on nix.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.gitea/workflows/arch.yml

@@ -1,4 +1,4 @@
-# Build the punktfunk-host / punktfunk-client / punktfunk-web pacman packages from
+# Build the punktfunk-host / punktfunk-client / punktfunk-web / punktfunk-scripting pacman packages from
 # packaging/arch/PKGBUILD and publish them to Gitea's Arch package registry, so Arch boxes
 # get new builds via `pacman -Syu`. Counterpart to deb.yml (apt) and rpm.yml (dnf/rpm-ostree).
 # Arch is rolling, so the packages build against whatever the archlinux:base-devel container
@@ -45,8 +45,9 @@ jobs:
             git nodejs rust clang cmake nasm pkgconf python vulkan-headers \
             gtk4 libadwaita sdl3 ffmpeg pipewire wayland libxkbcommon opus libei \
             mesa libglvnd unzip libarchive
-          # bun builds the punktfunk-web console AND is vendored as its runtime (PF_WITH_WEB=1);
-          # it's AUR-only on Arch, so bootstrap the official binary.
+          # bun builds the punktfunk-web console + the punktfunk-scripting runner AND is vendored as
+          # their runtime (PF_WITH_WEB=1 / PF_WITH_SCRIPTING=1); it's AUR-only on Arch, so bootstrap
+          # the official binary.
           command -v bun >/dev/null || {
             curl -fsSL https://bun.sh/install | bash
             install -m0755 "$HOME/.bun/bin/bun" /usr/local/bin/bun
@@ -105,7 +106,7 @@ jobs:
           sudo -u builder git config --global --add safe.directory "$PWD"
           mkdir -p dist && chown builder: dist
           cd packaging/arch
-          sudo -u builder env PF_SRCDIR="$GITHUB_WORKSPACE" PF_WITH_WEB=1 \
+          sudo -u builder env PF_SRCDIR="$GITHUB_WORKSPACE" PF_WITH_WEB=1 PF_WITH_SCRIPTING=1 \
             PF_PKGVER="$PF_PKGVER" PF_PKGREL="$PF_PKGREL" \
             CARGO_HOME="$CARGO_HOME" PKGDEST="$GITHUB_WORKSPACE/dist" \
             makepkg -f -d --holdver