ci: replace semantic-release with svu

* remove separate bump-semver and create-release workflows
* consolidate release process into single workflow triggered on main branch
* replace semantic-release tooling with svu for semantic version calculation
* combine version bumping and release creation into unified script

Author: csvenke

.github/workflows/main.yml

@@ -3,8 +3,7 @@ name: release
 on:
   workflow_dispatch:
   push:
-    tags:
-      - "v*"
+    branches: [main]
 
 permissions:
   contents: write
@@ -17,7 +16,7 @@ jobs:
         with:
           fetch-depth: 0
       - uses: DeterminateSystems/nix-installer-action@main
-      - name: Create release
-        run: nix run .#create-release
+      - name: Release
+        run: nix run .#release
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/release.yml

@@ -0,0 +1,27 @@
+{
+  writeShellApplication,
+  git,
+  svu,
+  goreleaser,
+}:
+
+writeShellApplication {
+  name = "release";
+  runtimeInputs = [
+    git
+    svu
+    goreleaser
+  ];
+  text = ''
+    NEXT_TAG=$(svu next)
+
+    if [ -n "$(git tag -l "$NEXT_TAG")" ]; then
+      echo "Tag $NEXT_TAG already exists, skipping release"
+      exit 0
+    fi
+
+    git tag "$NEXT_TAG"
+    git push --tags
+    goreleaser release --clean
+  '';
+}