ci: split test.yml into test-web.yml + test-go.yml, run on dev pushes

Operator wants CI to run on dev pushes (not just PR-to-main) but
path-scoped so Go-only diffs don't run web tests and vice versa. The
old test.yml ran everything on PR-to-main only; the new shape is two
focused workflows that each path-filter their own scope.

- test-web.yml — paths: web/**. Runs npm ci + npm run check + vitest.
  Drops the npm run build step (vitest doesn't need the bundle; the
  go:embed placeholder lives in web/build/index.html and never needs
  the test job to rebuild it).
- test-go.yml — paths: **/*.go, go.mod, go.sum, sqlc.yaml, internal/**,
  cmd/**. Runs go vet + golangci-lint + go test -short -race.

Both trigger on push to dev/main and PR to main. Tag pushes are not
covered — release.yml owns the tag-build path and tests have already
passed by the time a tag lands.

Drops the gomod-detect guard from test.yml — go.mod has been present
since M1 and is required for any Go file to exist anyway.

.forgejo/workflows/test-go.yml

@@ -0,0 +1,56 @@
+name: test-go
+
+# Go server: vet + golangci-lint + short race tests. Runs on push to
+# dev/main and PRs to main, scoped to Go-side files only — web-only or
+# Flutter-only diffs don't trigger this workflow.
+#
+# Integration tests needing Postgres/ffmpeg run locally via docker-compose;
+# they should guard with testing.Short() so this short-mode run skips them.
+#
+# `web/build/` has a committed placeholder index.html so go:embed succeeds
+# without needing the SPA to be freshly built. Real builds happen in
+# release.yml (container) and locally during dev.
+
+on:
+  push:
+    branches: [dev, main]
+    paths:
+      - '**/*.go'
+      - 'go.mod'
+      - 'go.sum'
+      - 'sqlc.yaml'
+      - 'internal/**'
+      - 'cmd/**'
+      - '.forgejo/workflows/test-go.yml'
+  pull_request:
+    branches: [main]
+    paths:
+      - '**/*.go'
+      - 'go.mod'
+      - 'go.sum'
+      - 'sqlc.yaml'
+      - 'internal/**'
+      - 'cmd/**'
+      - '.forgejo/workflows/test-go.yml'
+
+jobs:
+  test:
+    runs-on: go-ci
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Toolchain versions
+        run: |
+          go version
+          golangci-lint --version
+
+      - name: go vet
+        run: go vet ./...
+
+      - name: golangci-lint
+        run: golangci-lint run ./...
+
+      - name: go test (short, race)
+        run: go test -short -race ./...