DROP INDEX tool_bindings_live_package_bot;
CREATE UNIQUE INDEX tool_bindings_live_package_bot
    ON tool_bindings(package_row_id, bot_id)
    WHERE status IN ('installing', 'ready', 'switching', 'retiring');
CREATE TABLE package_transitions (
    id TEXT PRIMARY KEY,
    bot_id TEXT NOT NULL,
    computer_id TEXT NOT NULL REFERENCES computers(id) ON DELETE CASCADE,
    generation INTEGER NOT NULL,
    package_id TEXT NOT NULL,
    binding_id TEXT NOT NULL REFERENCES tool_bindings(id) ON DELETE CASCADE,
    source_id TEXT NOT NULL REFERENCES tool_packages(id) ON DELETE CASCADE,
    target_id TEXT NOT NULL REFERENCES tool_packages(id) ON DELETE CASCADE,
    retiring JSONB NOT NULL,
    status TEXT NOT NULL DEFAULT 'pending',
    schemas JSONB,
    created_at TIMESTAMPTZ NOT NULL DEFAULT now()
);
CREATE UNIQUE INDEX package_transition_pending
    ON package_transitions(bot_id, package_id) WHERE status IN ('pending','cancelling');