fix: set 0755 permissions on entrypoint script

chmod +x only adds execute bits but doesn't ensure read permission.
When the build umask strips read for group/other, the resulting 711
permissions prevent the vscode user from reading the shell script,
causing silent execution failure.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: bradleybeddoes

features/dbr/install.sh

@@ -106,7 +106,7 @@ echo "Installing entrypoint script..."
 mkdir -p /usr/local/share/dbr
 SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
 cp "${SCRIPT_DIR}/entrypoint.sh" /usr/local/share/dbr/entrypoint.sh
-chmod +x /usr/local/share/dbr/entrypoint.sh
+chmod 0755 /usr/local/share/dbr/entrypoint.sh
 
 echo "Done! dbr ${VERSION} installed to ${INSTALL_DIR}/dbr"
 echo "dbr-open hardlink created at ${INSTALL_DIR}/dbr-open"