Take Claude Desktop from the repository that now carries it

It was `panama app claude-desktop`: a source build, because nothing packaged it.
Upstream publishes an RPM repository now, so the exception shrinks to adding
that repository -- and the result upgrades with `dnf upgrade` along with
everything else instead of needing a slow rebuild every time a version ships.

That moves it out of setup/apps/ and into the third-party section of
install-packages, beside Bun, Claude Code and RustDesk. It also means it is part
of ./install for the first time. The reason it was kept out was the build: slow,
wants the network throughout, and fails on an upstream that moved, which is the
failure the interview exists to prevent. A dnf install is none of those, and the
default dock pins com.anthropic.Claude, so a fresh machine was shipping a pin
for something the install had never put there.

The repository is added with upstream's own setup script rather than a .repo
file written out here. A baseurl copied into this repository is a pin by another
name; the script is the part upstream keeps correct. Both halves are skipped
when already present, so a re-run costs nothing.

The desktop entry id does not change -- it is still com.anthropic.Claude -- so
the dock pin and the notification rules carry over untouched. The new package
drops the nodejs dependency, which is what used to hide the missing-npm bug the
launcher search contract guards; its comment said "depends" in the present
tense and now says what actually happened.

setup/apps/claude-desktop

@@ -1,28 +0,0 @@
-# Claude Desktop.
-#
-# Anthropic ships macOS and Windows only. This is a community wrapper that
-# downloads the official build, bundles Electron, and packages the result as a
-# proper Fedora RPM -- so what lands on the system is still a package dnf owns
-# and can remove, which is the part of the dnf/flatpak rule that matters most.
-#
-# The exception it needs is the build itself. There is no RPM or flatpak of
-# Claude Desktop to install, so the choice is building one or not having it.
-# Nothing is pinned: the default branch is built every time, and a failure is
-# reported rather than worked around. sunhat pinned versions and every pin was
-# a 404 within a release cycle.
-
-description="Claude Desktop, built into a Fedora RPM"
-repo="https://github.com/dewzor/claude-desktop-fedora.git"
-
-# The upstream script installs its own build dependencies and prints the RPM it
-# produced. It needs root because of that dependency install.
-build() {
-    sudo ./build-fedora.sh
-
-    local rpm
-    rpm="$(find build -name 'claude-desktop-*.rpm' -newermt '-1 hour' 2>/dev/null | head -1)"
-    [[ -n "$rpm" ]] || rpm="$(find . -name 'claude-desktop-*.rpm' 2>/dev/null | head -1)"
-    [[ -n "$rpm" ]] || { printf 'the build produced no RPM\n' >&2; return 1; }
-
-    sudo dnf install -y "$rpm"
-}