GrantPermissionTool

pm grant <pkg> <perm> — grant a runtime permission to an app without the user prompt. Idempotent. The permission must be one the app declared in its manifest. Treated as failure if the command exits non-zero or writes to stderr (not declared / not a runtime permission / etc.).

Privilege: requires a working ShellBackend.

Params: package_name (required), permission (required, fully-qualified).

On success the result map carries success (true), package_name, and permission.