Records phase 2 PR 5 of the module system: the lifecycle hooks a module
registers, how they are dispatched, and what a boot does to installed_modules.
MODULE_API.md 2.5 gains the reconcile's four steps in order, the rules that fall
out of them (the operator's `disabled` wins over any outcome; a bookkeeping
failure is not a boot failure; a module with no onBoot still reaches `started`;
a module whose onBoot threw gets no onShutdown), and why onBoot has no timeout
while onShutdown has a five-second budget -- shutdown races the process being
killed and boot does not.
4.4 gains the failure_stage table: every failure is recorded against the 4.3
step that produced it, so the admin panel can say where a module broke and not
only what the message was.
MODULE_SYSTEM.md 2.4 records the new rule for a row whose directory is gone, and
2.7 the PR 5 progress entry with its four decisions. BACKEND_DESIGN.md's
installed_modules section gains the write path now that one exists.
Co-Authored-By: Claude <noreply@anthropic.com>
