sagemathgh-39286: Migrate pyright workflow to use conda
    
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Simplifies the setup a bit and one step closer to independence on sage-
the-distro. Also updates the pyright action

### 📝 Checklist

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- [ ] The title is concise and informative.
- [ ] The description explains in detail what this PR is about.
- [ ] I have linked a relevant issue or discussion.
- [ ] I have created tests covering the changes.
- [ ] I have updated the documentation and checked the documentation
preview.

### ⌛ Dependencies

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URL: sagemath#39286
Reported by: Tobias Diez
Reviewer(s): Dima Pasechnik

.github/workflows/pyright.yml

@@ -1,12 +1,12 @@
-name: Static check with Pyright
+name: Static type check
 
 on:
-  pull_request:
   merge_group:
   push:
     branches:
       - master
       - develop
+  pull_request:
   workflow_dispatch:
     # Allow to run manually
 
@@ -18,67 +18,41 @@ concurrency:
 jobs:
   pyright:
     runs-on: ubuntu-latest
-    container: ghcr.io/sagemath/sage/sage-ubuntu-noble-standard-with-targets:dev
     steps:
       - name: Checkout
-        id: checkout
         uses: actions/checkout@v4
 
-      - name: Update system packages
-        id: prepare
-        run: |
-          export PATH="build/bin:$PATH"
-          eval $(sage-print-system-package-command auto update)
-          eval $(sage-print-system-package-command auto --spkg --yes --no-install-recommends install git)
-
-      - name: Install GH CLI
-        uses: dev-hanz-ops/[email protected]
-        with:
-          gh-cli-version: 2.32.0
-
       - name: Merge CI fixes from sagemath/sage
         run: |
-          git config --global --add safe.directory "$GITHUB_WORKSPACE"
           .ci/merge-fixes.sh
-
-      - name: Add prebuilt tree as a worktree
-        id: worktree
-        run: |
-          set -ex
-          .ci/retrofit-worktree.sh worktree-image /sage
-
-      - name: Incremental build (sagelib deps)
-        id: incremental
-        run: |
-          # Now re-bootstrap and build. The build is incremental because we were careful with the timestamps.
-          # pyright does not need a built sagelib; it only needs
-          # the libraries from which sagelib imports.
-          ./bootstrap && make sagelib-build-deps
-        working-directory: ./worktree-image
         env:
-          MAKE: make -j2 --output-sync=recurse
-          SAGE_NUM_THREADS: 2
+          GH_TOKEN: ${{ github.token }}
 
-      - name: Static code check with pyright
-        uses: jakebailey/pyright-action@v1
+      - name: Cache conda packages
+        uses: actions/cache@v4
         with:
-          version: 1.1.332
-          # Many warnings issued by pyright are not yet helpful because there is not yet enough type information.
-          no-comments: true
-          working-directory: ./worktree-image
-        env:
-          # To avoid out of memory errors
-          NODE_OPTIONS: --max-old-space-size=8192
+          path: ~/conda_pkgs_dir
+          key:
+            ${{ runner.os }}-conda-${{ hashFiles('environment-3.11-linux.yml') }}
 
-      - name: Static code check with pyright (annotated)
-        if: (success() || failure()) && steps.incremental.outcome == 'success'
-        uses: jakebailey/pyright-action@v1
+      - name: Setup Conda environment
+        uses: conda-incubator/setup-miniconda@v3
+        with:
+          python-version: 3.11
+          miniforge-version: latest
+          use-mamba: true
+          channels: conda-forge
+          channel-priority: true
+          activate-environment: sage-dev
+          environment-file: environment-3.11-linux.yml
+
+        # No need to build sagelib; pyright only needs the libraries from which sagelib imports
+
+      - name: Static code check with pyright
+        uses: jakebailey/[email protected]
         with:
           version: 1.1.332
-          # Issue errors
-          no-comments: false
-          level: error
-          working-directory: ./worktree-image
+          annotate: "errors"
         env:
           # To avoid out of memory errors
           NODE_OPTIONS: --max-old-space-size=8192