docs(audit): add /goal prompt for autonomous milestone execution
Self-contained prompt to drive M1..M8 execution against the roadmap.
Embeds the per-milestone loop: branch -> brainstorm -> writing-plans ->
subagent-driven-development -> verify (tests gate) -> merge --no-ff ->
update downstream roadmap sections with realities learned -> proceed.
Honors the user-memory feedback (bundling cadence, UI rules, form layout,
recommendations-first) and the locked invariants (prose anchors not §N,
CachedCallTelemetry not CachedOperationTelemetry, audit failures never
abort actions, append-only, ForwardState purge invariant, no push, v1.x
features stay deferred). Termination criteria are explicit.
e8ae0e8544