gh-40516: Simplify macos CI and make it more robust
    
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The macos workflow currently uses various interconnected levels of
abstraction: ci-macos.yml > meson.yml > tox > make.
But in the end, its simply calling the usual `bootstrap + configure +
make build` commands. So we simplify the whole construction in the CI,
to do exactly that and nothing more.

(Note that it currently is supposed to also install certain optional and
experimental packages; but looking at the log this is actually not
working https://github.com/sagemath/sage/actions/runs/16538105107/job/46
778843389 - so this is left for a followup PR)

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- [ ] I have created tests covering the changes.
- [ ] I have updated the documentation and checked the documentation
preview.

### ⌛ Dependencies

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URL: #40516
Reported by: Tobias Diez
Reviewer(s): Dima Pasechnik

Author: Release Manager

.github/workflows/ci-macos.yml

@@ -21,56 +21,51 @@ on:
   pull_request:
     paths:
       - '.github/workflows/ci-macos.yml'
-      - '.github/workflows/macos.yml'
   push:
     tags:
       - '*'
   workflow_dispatch:
     # Allow to run manually
 
-env:
-  TARGETS_PRE: all-sage-local
-  TARGETS: build
-  TARGETS_OPTIONAL: ptest
-
 jobs:
-  stage-1:
-    uses: ./.github/workflows/macos.yml
-    with:
-      stage: "1"
-      timeout: 14400
-
-  stage-2:
-    uses: ./.github/workflows/macos.yml
-    with:
-      stage: "2"
-    needs: [stage-1]
-    if: ${{ success() || failure() }}
+  macos:
+    name: Build and Test (macos-${{ matrix.version }})
+    runs-on: macos-${{ matrix.version }}
+    strategy:
+      fail-fast: false
+      matrix:
+        version:
+          - '13'
+          - '14'
+          - '15'
 
-  stage-2-optional-0-o:
-    uses: ./.github/workflows/macos.yml
-    with:
-      stage: "2-optional-0-o"
-    needs: [stage-2]
-    if: ${{ success() || failure() }}
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
 
-  stage-2-optional-p-z:
-    uses: ./.github/workflows/macos.yml
-    with:
-      stage: "2-optional-p-z"
-    needs: [stage-2-optional-0-o]
-    if: ${{ success() || failure() }}
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.13"
+        
+      - name: Install test prerequisites
+        run: python -m pip install tox
 
-  stage-2-experimental-0-o:
-    uses: ./.github/workflows/macos.yml
-    with:
-      stage: "2-experimental-0-o"
-    needs: [stage-2-optional-p-z]
-    if: ${{ success() || failure() }}
+      - name: Install dependencies
+        run: |
+          eval $(build/bin/sage-print-system-package-command homebrew update)
+          eval $(build/bin/sage-print-system-package-command homebrew --yes --ignore-missing install $(build/bin/sage-get-system-packages homebrew _bootstrap _prereq $(build/bin/sage-package list :standard:)))
 
-  stage-2-experimental-p-z:
-    uses: ./.github/workflows/macos.yml
-    with:
-      stage: "2-experimental-p-z"
-    needs: [stage-2-experimental-0-o]
-    if: ${{ success() || failure() }}
+      - name: Build
+        run: |
+          source ./.homebrew-build-env
+          ./bootstrap
+          ./configure --enable-download-from-upstream-url
+          make build V=0
+        env:
+          MAKE: 'make -j6'
+      
+      - name: Test
+        run: |
+          source ./.homebrew-build-env # Needed so that runtime cython can find the dependencies
+          ./sage -t --all -p4
+    

.github/workflows/macos.yml

@@ -1006,8 +1006,7 @@ This is defined in the files
 - :sage_root:`.github/workflows/ci-distro.yml`
   (which calls :sage_root:`.github/workflows/docker.yml`) and
 
-- :sage_root:`.github/workflows/ci-macos.yml`
-  (which calls :sage_root:`.github/workflows/macos.yml`).
+- :sage_root:`.github/workflows/ci-macos.yml`.
 
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