ci: install the clippy component in the rust image

rust:1.91-bookworm ships without clippy, so the clippy step died with
'cargo-clippy is not installed for the toolchain' after all 39 tests
passed. Also pushes the watcher fix (1=success 2=failure in Forgejo job
statuses, not action_run's numbering).

.forgejo/workflows/ci.yml

@@ -40,6 +40,7 @@ jobs:
             sh -euxc 'mkdir -p /src && tar xzf - -C /src && cd /src \
               && apt-get update \
               && apt-get install -y --no-install-recommends pkg-config libssl-dev \
+              && rustup component add clippy \
               && cargo test --locked \
               && cargo clippy --locked --all-targets -- -D warnings'
           tar czf - --exclude=./target --exclude=./.git --exclude=./.worktrees . \