make: Include "version.txt" in tarball.

.github/workflows/tarball.yml

@@ -67,6 +67,7 @@ jobs:
         mkdir -p tmp
         tar xvf nextcloud-spreed-signaling*.tar.gz --strip-components=1 -C tmp
         [ -d "tmp/vendor" ] || exit 1
+        [ -f "tmp/version.txt" ] || exit 1
 
     - name: Build
       run: |
@@ -77,6 +78,11 @@ jobs:
           echo "Found unknown version: $UNKNOWN"; \
           exit 1; \
         fi
+        UNKNOWN=$(./tmp/bin/proxy -version | grep unknown || true)
+        if [ -n "$UNKNOWN" ]; then \
+          echo "Found unknown version: $UNKNOWN"; \
+          exit 1; \
+        fi
 
   test:
     strategy:

Makefile

@@ -194,7 +194,7 @@ vendor: go.mod go.sum
 	rm -rf $(VENDORDIR)
 	$(GO) mod vendor
 
-tarball: vendor
+tarball: vendor | $(TMPDIR)
 	git archive \
 		--prefix=nextcloud-spreed-signaling-$(TARVERSION)/ \
 		-o nextcloud-spreed-signaling-$(TARVERSION).tar \
@@ -204,6 +204,12 @@ tarball: vendor
 		--mtime="$(shell git log -1 --date=iso8601-strict --format=%cd HEAD)" \
 		--transform "s//nextcloud-spreed-signaling-$(TARVERSION)\//" \
 		vendor
+	echo "$(TARVERSION)" > "$(TMPDIR)/version.txt"
+	tar rf nextcloud-spreed-signaling-$(TARVERSION).tar \
+		-C "$(TMPDIR)" \
+		--mtime="$(shell git log -1 --date=iso8601-strict --format=%cd HEAD)" \
+		--transform "s//nextcloud-spreed-signaling-$(TARVERSION)\//" \
+		version.txt
 	gzip --force nextcloud-spreed-signaling-$(TARVERSION).tar
 
 dist: tarball