plotext: add build-plotext.yml for riscv64 wheels (#1102)

* **Package**: `plotext`
* **Version**: `6.0.0`
* **Source**: https://github.com/piccolomo/plotext
* **Docs**: https://github.com/piccolomo/plotext

Compiles a small C++ kernel (`plotext/_kernel/cpp/kernel.cpp`) that plotext loads with ctypes at runtime; the `py3-none-<platform>` tag is real per-arch compiled content, not a pure-Python wheel, and upstream ships none for riscv64.

Mirrors [upstream's `wheels.yml`](https://github.com/piccolomo/plotext/blob/6.0.0/.github/workflows/wheels.yml).

**Differs from upstream**
- Test command runs `windows.yml`'s fuller unit test modules - the Linux job only smoke-tests the import.

**Matrix**: single `cp312` build - `setup.py`'s `get_tag()` forces `py3-none-<platform>`, so one build serves every interpreter.

**Testing**
- Runs upstream's own unit tests (primitives, plots, dates, fixed_bugs, hashes, prettydoc) instead of pyproject.toml's one-line import check.

**License**: OK

Built on cp312; 61 passed.

Author: luhenry

.github/workflows/build-plotext.yml

@@ -0,0 +1,91 @@
+# SPDX-FileCopyrightText: 2026 The RISE Project
+# SPDX-License-Identifier: MIT
+---
+# This workflow is based on: https://github.com/piccolomo/plotext/blob/6.0.0/.github/workflows/wheels.yml
+name: Build plotext wheels (riscv64)
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'plotext version to build (git tag, e.g. 6.0.0)'
+        required: true
+        default: '6.0.0'
+  pull_request:
+    paths:
+      - '.github/workflows/build-plotext.yml'
+
+concurrency:
+  group: ${{ github.workflow }}-${{ inputs.version || '6.0.0' }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read  # to fetch code (actions/checkout)
+
+env:
+  PLOTEXT_VERSION: ${{ inputs.version || '6.0.0' }}
+  MANYLINUX_RISCV64_IMAGE: quay.io/pypa/manylinux_2_39_riscv64
+
+jobs:
+  setup:
+    uses: $/.github/workflows/_setup.yml
+
+  build_wheels:
+    needs: [setup]
+    name: Build plotext ${{ inputs.version || '6.0.0' }} py3-none-manylinux_riscv64
+    runs-on: ubuntu-24.04-riscv
+
+    steps:
+      - name: Checkout plotext ${{ env.PLOTEXT_VERSION }}
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
+        with:
+          repository: piccolomo/plotext
+          ref: ${{ env.PLOTEXT_VERSION }}
+          persist-credentials: false
+
+      - name: Build wheel
+        uses: pypa/cibuildwheel@1828c10ab37f080699c7b81cea34097c684a7074  # v4.2.0
+        with:
+          output-dir: wheelhouse/
+          # setup.py's wheel_of_this_system.get_tag() tags the wheel py3-none-<platform>: the
+          # C++ kernel it compiles is loaded by ctypes, not tied to any interpreter, so one
+          # build serves every Python.
+          only: cp312-manylinux_riscv64
+        env:
+          CIBW_MANYLINUX_RISCV64_IMAGE: ${{ env.MANYLINUX_RISCV64_IMAGE }}
+          # Mirrors upstream's own windows.yml unit-test invocation (the Linux wheels.yml
+          # job only runs pyproject.toml's one-line import smoke test).
+          CIBW_TEST_COMMAND: >-
+            python -m unittest plotext._tests.primitives plotext._tests.plots
+            plotext._tests.dates plotext._tests.fixed_bugs plotext._tests.hashes
+            plotext.prettydoc._tests.docs plotext.prettydoc._tests.hashes -v
+
+      - name: Check the wheel carries a riscv64 kernel.so
+        run: |
+          whl=$(ls wheelhouse/*.whl)
+          python3 - "$whl" <<'EOF'
+          import sys, zipfile
+          whl = sys.argv[1]
+          target = "plotext/_kernel/cpp/kernel.so"
+          names = zipfile.ZipFile(whl).namelist()
+          if target not in names:
+              raise SystemExit(f"error: {target} missing from {whl}")
+          zipfile.ZipFile(whl).extract(target, "kernel_check")
+          EOF
+          file kernel_check/plotext/_kernel/cpp/kernel.so | tee /dev/stderr | grep -q 'RISC-V'
+
+      - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7.0.1
+        with:
+          name: plotext-${{ env.PLOTEXT_VERSION }}-py3-none-manylinux_riscv64
+          path: wheelhouse/*.whl
+          if-no-files-found: error
+
+  publish:
+    name: Publish plotext ${{ inputs.version || '6.0.0' }}
+    needs: [setup, build_wheels]
+    permissions:
+      contents: write
+      pull-requests: write
+    uses: $/.github/workflows/_publish-wheel.yml
+    with:
+      artifact-pattern: plotext-${{ inputs.version || '6.0.0' }}-*-manylinux_riscv64