docs: fix audit-found drift (status enum, env, limitations, action layout)

Audit follow-up. ARCHITECTURE: status now 'In production', authoritative
note that server actions are per-domain under lib/actions/* (no monolithic
lib/actions.ts), rewrote stale Known Limitations (test suite exists;
PayPal sync route; social auth wired; webhooks signing-only; single-space
assumption), fixed env table (removed phantom SUPABASE_JWT_SECRET, added
SECRETS_ENCRYPTION_KEY/OAuth). DATABASE_SCHEMA/DB_SCHEMA_MAP: ~43 tables /
migrations through 038; space_members.status is member_status enum default
'unverified' (was wrongly 'active'); fixed the active/pending flow text.
README: webhook wording matches WEBHOOKS.md. API_REFERENCE: real
lib/actions/* path + 4 previously-undocumented actions. createSecret docs
were already correct (ADMIN_ROLES = admin+board) -- left as-is.

README.md

@@ -24,7 +24,7 @@ A multi-tenant operating system for hackerspaces, makerspaces, and member-run sh
 - **Governance.** Proposals with quorum, vote tracking and expiry; incident reports with anonymous reporter tracking by token; versioned policy library; member forum with polymorphic comments.
 - **Communications.** Multi-channel chat with realtime delivery.
 - **Recruitment.** Public-facing recruitment page per space.
-- **API.** PostgREST-generated REST for every table, gated by RLS. Optional webhooks with HMAC-signed deliveries.
+- **API.** PostgREST-generated REST for every table, gated by RLS. Webhook HMAC signing contract + secret rotation are defined; per-event delivery is a follow-up (see [docs/WEBHOOKS.md](./docs/WEBHOOKS.md)).
 
 ## Stack