ci: correct the tools the viewer archive is said to carry, and two dead conditions

rugnux_scale and azint have not been separate binaries since they became rugnux --scale
and rugnux --azint-only; the viewer component carries rugnux, jfjoch_extract_hkl and
jfjoch_recompress.

Two job conditions tested github.ref_type against 'workflow_dispatch'. ref_type is only
ever 'branch' or 'tag', so that test never matched and never did anything: build-rpm's
whole condition was that test, and half of the unit-test one was. Both jobs ran on a
dispatch, as the release flow needs them to. Drop the dead tests rather than repair them
- the behaviour they read as intending is not the behaviour that is wanted - and write
down why unit-tests is skipped on a tag, which is the part that is deliberate: the
dispatch run is the one that tests, and the tag it creates only rebuilds and uploads.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

.gitea/workflows/build_and_test.yml

@@ -43,7 +43,11 @@ jobs:
   unit-tests:
     name: Unit tests
     runs-on: jfjoch_rocky8
-    if: github.ref_type != 'tag' && github.ref_type != 'workflow_dispatch'
+    # Not on a tag, on purpose. Releasing is a two-step dance because artifacts do not carry between
+    # runs: the manual dispatch below runs the whole CI (this job included) and then creates the tag,
+    # and the tag push re-runs the workflow only to rebuild and upload. The tag run has therefore
+    # already been tested by the dispatch run it came from.
+    if: github.ref_type != 'tag'
     container:
       image: gitea.psi.ch/leonarski_f/jfjoch_rocky8:2511
       options: --gpus all
@@ -160,8 +164,8 @@ jobs:
         run: |
           cd build
           # Build the whole viewer-only tree, not just the GUI: the "viewer" CPack component also
-          # contains the portable CLI tools (rugnux/rugnux_scale/azint/recompress/extract_hkl),
-          # which must exist on disk before cpack installs the component.
+          # contains the portable CLI tools (rugnux, jfjoch_extract_hkl, jfjoch_recompress), which
+          # must exist on disk before cpack installs the component.
           ninja -j16
           cpack
       - name: Upload viewer tgz to release
@@ -186,7 +190,6 @@ jobs:
           done
   build-rpm:
     name: build:rpm (${{ matrix.distro }})
-    if: github.ref_type != 'workflow_dispatch'
     runs-on: ${{ matrix.runner }}
     strategy:
       fail-fast: false