CI: Add zsh-based build framework files for macOS

.github/scripts/utils.zsh/read_codesign_pass

@@ -0,0 +1,24 @@
+autoload -Uz read_codesign read_codesign_user log_info log_warning
+
+if (( ! ${+CODESIGN_IDENT} )) {
+  read_codesign
+}
+
+if (( ! ${+CODESIGN_IDENT_USER} )) {
+  read_codesign_user
+}
+
+log_info 'Setting up password for notarization keychain...'
+if (( ! ${+CODESIGN_IDENT_PASS} )) {
+  read -s CODESIGN_IDENT_PASS'?Apple Developer ID password: '
+}
+
+print ''
+log_info 'Setting up notarization keychain...'
+log_warning "
+ + Your Apple ID and an app-specific password is necessary for notarization from CLI
+ + This password will be stored in your macOS keychain under the identifier
+   'OBS-Codesign-Password' with access Apple's 'altool' only.
+
+"
+xcrun notarytool store-credentials 'OBS-Codesign-Password' --apple-id "${CODESIGN_IDENT_USER}" --team-id "${CODESIGN_TEAM}" --password "${CODESIGN_IDENT_PASS}"