ci: build frontend bundle before Go compile in release.yml + Dockerfile

Phase 8 cut all panel HTML routes over to web/dist/ and embedded the
Vite bundle into the Go binary via //go:embed all:dist. web/dist/ is
.gitignored, so on a fresh CI checkout it doesn't exist — every Go
build since Phase 8 has been failing with "pattern dist: no matching
files found" or producing a binary that 404s on first asset request.

release.yml: add a setup-node@v4 + npm ci + npm run build trio before
the existing go build step in both the Linux matrix job (7 arches)
and the Windows job. npm cache is keyed on frontend/package-lock.json.

Dockerfile: add a node:22-alpine frontend stage that runs npm ci +
npm run build and emits to /src/web/dist (via vite.config.js's outDir).
The golang builder stage then COPY --from=frontend /src/web/dist into
./web/dist before the go build, so embed.FS sees the bundle.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

.github/workflows/release.yml

@@ -83,6 +83,23 @@ jobs:
           go-version-file: go.mod
           check-latest: true
 
+      # Frontend dist must be built BEFORE go build — Go's //go:embed
+      # all:dist directive in web/web.go requires web/dist/ to exist
+      # at compile time. web/dist/ is .gitignored, so on a fresh CI
+      # checkout it doesn't exist until vite emits it.
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+          cache: 'npm'
+          cache-dependency-path: frontend/package-lock.json
+
+      - name: Build frontend bundle
+        run: |
+          npm ci
+          npm run build
+        working-directory: frontend
+
       - name: Build 3X-UI
         run: |
           export CGO_ENABLED=1
@@ -209,6 +226,23 @@ jobs:
           go-version-file: go.mod
           check-latest: true
 
+      # Frontend dist must be built BEFORE go build — see comment on the
+      # Linux job above. This step is identical except npm runs on the
+      # Windows runner here.
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+          cache: 'npm'
+          cache-dependency-path: frontend/package-lock.json
+
+      - name: Build frontend bundle
+        shell: pwsh
+        run: |
+          npm ci
+          npm run build
+        working-directory: frontend
+
       - name: Install MSYS2
         uses: msys2/setup-msys2@v2
         with:

Dockerfile

@@ -1,3 +1,20 @@
+# ========================================================
+# Stage: Frontend (Vite)
+# ========================================================
+# web/dist/ is .gitignored and embedded into the Go binary via
+# //go:embed all:dist in web/web.go, so the SPA bundle MUST be built
+# before the Go compile step. We build it in its own stage so the
+# Go builder image doesn't need Node installed.
+FROM node:22-alpine AS frontend
+WORKDIR /src/frontend
+COPY frontend/package.json frontend/package-lock.json ./
+RUN npm ci
+COPY frontend/ ./
+RUN npm run build
+# Vite outDir is set to ../web/dist (see frontend/vite.config.js), so
+# the bundle lands at /src/web/dist — that's what we copy into the
+# next stage.
+
 # ========================================================
 # Stage: Builder
 # ========================================================
@@ -12,6 +29,7 @@ RUN apk --no-cache --update add \
   unzip
 
 COPY . .
+COPY --from=frontend /src/web/dist ./web/dist
 
 ENV CGO_ENABLED=1
 ENV CGO_CFLAGS="-D_LARGEFILE64_SOURCE"