ci: ship per-march variants (v2/v3/v4) as individual artifacts

Replaces the single Linux + single Windows tarball with six self-
contained variants — three µarch levels × two OSes. End users on the
Releases page see them as six individually-downloadable archives:

  crafter-build-{linux,windows}-x86_64-{v2,v3,v4}.{tar.gz,zip}

Pick the v-level your CPU supports:
  v2: SSE4.2 baseline (every x86_64 since ~2011)
  v3: AVX2 + FMA + BMI (Intel Haswell+, AMD Excavator+, ~2013+)
  v4: AVX-512 (Skylake-X+, recent server-class)

How: the bootstrap binary stays at v2 because the CI SBC (N5105 / Tremont,
no AVX) can't execute v3 or v4 instructions and would crash before it
could rebuild itself for higher levels. Once bootstrap's done, the same
v2 binary is re-invoked with CRAFTER_BUILD_MARCH overridden per variant
to produce v2/v3/v4 outputs. Same again with --target=x86_64-w64-mingw32
for the Windows variants. ExternalDependency cache keys on (url, target,
march) already so glslang gets built per variant; subsequent CI runs hit
the cache.

Also drops the wrapper zip from workflow artifacts: instead of one
upload-artifact call producing crafter-build.zip containing six archives,
there's now one call per archive. The PR / run page shows six small
downloads named for what they are.

forgejo-release continues to upload release-dir/* as individual assets,
so the Releases page already has the right shape — this just brings the
workflow artifact UX in line.

Bumped the glslang cache key to v2 (one-time invalidation) since the
cache layout now needs space for six glslang builds rather than two.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.forgejo/workflows/ci.yaml

@@ -12,10 +12,11 @@ jobs:
     runs-on: arch-latest
     env:
       # x86-64-v2 = SSE4.2 baseline; runs on the CI SBC (Intel N5105 / Tremont,
-      # no AVX) and on essentially every x86_64 CPU since ~2011. v3 is out —
+      # no AVX) and on essentially every x86_64 CPU since ~2011. The bootstrap
-      # it requires AVX2 the SBC doesn't have, so the bootstrap binary
+      # MUST stay v2 — anything higher would emit instructions the SBC can't
-      # wouldn't even run there. mtune=generic keeps codegen balanced across
+      # execute and the bootstrap binary itself would crash before it could
-      # consumer CPUs.
+      # rebuild for higher levels. v3/v4 variants are produced from this v2
+      # bootstrap by re-running it with CRAFTER_BUILD_MARCH overridden.
       CRAFTER_BUILD_MARCH: x86-64-v2
       CRAFTER_BUILD_MTUNE: generic
     steps:
@@ -50,56 +51,85 @@ jobs:
           persist-credentials: true
 
       - name: Cache glslang clone+build
+        # Cache covers crafter-build's per-(target, march) external dep cache.
+        # First run builds glslang up to 6 times (3 marches × 2 targets); the
+        # cache makes subsequent runs reuse those builds.
         uses: actions/cache@v4
         with:
           path: |
             ~/.cache/crafter.build/external
-          key: glslang-${{ runner.os }}-v1
+          key: glslang-${{ runner.os }}-v2
 
       - name: Bootstrap (build.sh)
         run: ./build.sh
 
-      - name: Self-rebuild via crafter-build (Linux)
-        run: CRAFTER_BUILD_HOME=$PWD/share/crafter-build ./bin/crafter-build
-
       - name: Run tests
         run: CRAFTER_BUILD_HOME=$PWD/share/crafter-build ./bin/crafter-build test
 
-      - name: Cross-compile for Windows (mingw32)
+      - name: Build Linux x86-64-v2 (matches bootstrap)
+        run: CRAFTER_BUILD_HOME=$PWD/share/crafter-build ./bin/crafter-build
+
+      - name: Build Linux x86-64-v3
+        run: CRAFTER_BUILD_HOME=$PWD/share/crafter-build CRAFTER_BUILD_MARCH=x86-64-v3 ./bin/crafter-build
+
+      - name: Build Linux x86-64-v4
+        run: CRAFTER_BUILD_HOME=$PWD/share/crafter-build CRAFTER_BUILD_MARCH=x86-64-v4 ./bin/crafter-build
+
+      - name: Build Windows x86-64-v2 (mingw)
         run: CRAFTER_BUILD_HOME=$PWD/share/crafter-build ./bin/crafter-build --target=x86_64-w64-mingw32
 
+      - name: Build Windows x86-64-v3 (mingw)
+        run: CRAFTER_BUILD_HOME=$PWD/share/crafter-build CRAFTER_BUILD_MARCH=x86-64-v3 ./bin/crafter-build --target=x86_64-w64-mingw32
+
+      - name: Build Windows x86-64-v4 (mingw)
+        run: CRAFTER_BUILD_HOME=$PWD/share/crafter-build CRAFTER_BUILD_MARCH=x86-64-v4 ./bin/crafter-build --target=x86_64-w64-mingw32
+
       - name: Package artifacts
         run: |
           set -eux
           mkdir -p dist
 
-          # Linux: bin/, lib/, share/ at archive root
+          # 6 archives — 3 marches × 2 OSes. Each is self-contained: the
-          stage_lin=$(mktemp -d)
+          # Linux launcher is statically linked; the Windows launcher has
-          mkdir -p "$stage_lin/bin" "$stage_lin/lib"
+          # crafter-build.dll + libcrafter-build.dll.a alongside the exe.
-          cp bin/crafter-build "$stage_lin/bin/"
+          for march in x86-64-v2 x86-64-v3 x86-64-v4; do
-          cp lib/libcrafter-build.a "$stage_lin/lib/"
+            stage_lin=$(mktemp -d)
-          cp -r share "$stage_lin/"
+            mkdir -p "$stage_lin/bin" "$stage_lin/lib"
-          tar czf dist/crafter-build-linux-x86_64.tar.gz -C "$stage_lin" .
+            cp "bin/crafter.build-exe-x86_64-pc-linux-gnu-$march/crafter-build" "$stage_lin/bin/"
+            cp "bin/crafter.build-lib-x86_64-pc-linux-gnu-$march/libcrafter-build.a" "$stage_lin/lib/"
+            cp -r share "$stage_lin/"
+            tar czf "dist/crafter-build-linux-x86_64-$march.tar.gz" -C "$stage_lin" .
 
-          # Windows: bin/ contents (exe + auto-bundled mingw DLLs) and share/.
+            stage_win=$(mktemp -d)
-          # The output dir is named by march, which matches the env var, not
+            mkdir -p "$stage_win/bin"
-          # the literal "native" — keep these in sync.
+            cp "bin/crafter.build-exe-x86_64-w64-mingw32-$march"/* "$stage_win/bin/"
-          stage_win=$(mktemp -d)
+            cp -r share "$stage_win/"
-          mkdir -p "$stage_win/bin"
+            (cd "$stage_win" && zip -r "$GITHUB_WORKSPACE/dist/crafter-build-windows-x86_64-$march.zip" .)
-          cp "bin/crafter.build-exe-x86_64-w64-mingw32-${CRAFTER_BUILD_MARCH}"/* "$stage_win/bin/"
+          done
-          cp -r share "$stage_win/"
-          (cd "$stage_win" && zip -r "$GITHUB_WORKSPACE/dist/crafter-build-windows-x86_64.zip" .)
 
           ls -la dist/
 
-      - name: Upload workflow artifacts
+      # Upload each archive as its own workflow artifact (one upload per file)
-        # v4+ uses a GHES-only upload API Forgejo Actions doesn't implement;
+      # so users browsing the PR / run page get six small, individually-named
-        # v3 stays on the older API that works on Forgejo.
+      # downloads instead of one wrapper zip containing the lot.
+      - name: Upload Linux v2 artifact
         uses: actions/upload-artifact@v3
-        with:
+        with: { name: crafter-build-linux-x86_64-v2, path: dist/crafter-build-linux-x86_64-v2.tar.gz, if-no-files-found: error }
-          name: crafter-build
+      - name: Upload Linux v3 artifact
-          path: dist/
+        uses: actions/upload-artifact@v3
-          if-no-files-found: error
+        with: { name: crafter-build-linux-x86_64-v3, path: dist/crafter-build-linux-x86_64-v3.tar.gz, if-no-files-found: error }
+      - name: Upload Linux v4 artifact
+        uses: actions/upload-artifact@v3
+        with: { name: crafter-build-linux-x86_64-v4, path: dist/crafter-build-linux-x86_64-v4.tar.gz, if-no-files-found: error }
+      - name: Upload Windows v2 artifact
+        uses: actions/upload-artifact@v3
+        with: { name: crafter-build-windows-x86_64-v2, path: dist/crafter-build-windows-x86_64-v2.zip, if-no-files-found: error }
+      - name: Upload Windows v3 artifact
+        uses: actions/upload-artifact@v3
+        with: { name: crafter-build-windows-x86_64-v3, path: dist/crafter-build-windows-x86_64-v3.zip, if-no-files-found: error }
+      - name: Upload Windows v4 artifact
+        uses: actions/upload-artifact@v3
+        with: { name: crafter-build-windows-x86_64-v4, path: dist/crafter-build-windows-x86_64-v4.zip, if-no-files-found: error }
 
       - name: Update rolling 'latest' tag
         if: (github.event_name == 'push' || github.event_name == 'workflow_dispatch') && github.ref == 'refs/heads/master'
@@ -110,6 +140,9 @@ jobs:
           git push origin latest --force
 
       - name: Publish rolling 'latest' release
+        # forgejo-release uploads each file in release-dir as a separate
+        # release asset, so the Releases page shows six individually
+        # downloadable archives — pick the v-level matching your CPU.
         if: (github.event_name == 'push' || github.event_name == 'workflow_dispatch') && github.ref == 'refs/heads/master'
         uses: https://code.forgejo.org/actions/forgejo-release@v2
         with: