ci: disable macOS release and nightly builds until signing key is available

Comment out macOS matrix entries in release and nightly workflows.
CI build verification is kept since it doesn't require signing.

Signed-off-by: Claude <noreply@anthropic.com>

https://claude.ai/code/session_018FzhWeoXR2NTxZ4LXQ1NJS
Signed-off-by: Claude <noreply@anthropic.com>

Author: claude

.github/workflows/nightly.yml

@@ -23,8 +23,9 @@ jobs:
             target: x86_64-unknown-linux-gnu
           - os: windows-latest
             target: x86_64-pc-windows-msvc
-          - os: macos-latest
-            target: aarch64-apple-darwin
+          # macOS build disabled until signing key is available
+          # - os: macos-latest
+          #   target: aarch64-apple-darwin
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v4

.github/workflows/release.yml

@@ -50,12 +50,13 @@ jobs:
           - os: windows-latest
             target: x86_64-pc-windows-msvc
             artifact: windows
-          - os: macos-latest
-            target: aarch64-apple-darwin
-            artifact: macos-arm
-          - os: macos-15
-            target: x86_64-apple-darwin
-            artifact: macos-intel
+          # macOS builds disabled until signing key is available
+          # - os: macos-latest
+          #   target: aarch64-apple-darwin
+          #   artifact: macos-arm
+          # - os: macos-15
+          #   target: x86_64-apple-darwin
+          #   artifact: macos-intel
 
     runs-on: ${{ matrix.os }}
     permissions: