docs(roadmap): insert phase 18.1 payment gateway subscriptions

.planning/ROADMAP.md

@@ -1020,6 +1020,27 @@ Plans:
 Plans:
 - [ ] TBD (run $gsd-plan-phase 18 to break down)
 
+### Phase 18.1: Payment Gateway Subscriptions (INSERTED)
+
+**Goal:** The generic core of `Golem15.PaymentGatewaySubscriptions` and pgstripe's subscription gateway and webhook run on SummerCMS. Horoskopia's subscription flow (plans, checkout, Stripe webhook, `golem15.pgsub.*` events, cancel and portal) works as it does on PHP.
+**Mode:** mvp
+**Depends on:** Phase 18
+**Repos:** `sm-paymentgatewaysubscriptions-plugin` (new, under `git.golem15.com/golem15/`); a subpackage of `sm-pgstripe-plugin`; `vue-paymentgateway-layer`; `summercms.go` only if a framework feature is missing
+**Port sources:** `Golem15.PaymentGatewaySubscriptions` at `ac3d73c` plus `5fb9dac`, and pgstripe `8b47457`, at `/media/nvme/dev/golem15/horoskopia.eu/plugins/golem15/{paymentgatewaysubscriptions,pgstripe}`. Quotify's lead fees, featured placements and analytics are not ported here.
+**Requirements**: TBD
+**Success Criteria** (what must be TRUE):
+
+  1. Subscription and SubscriptionPlan port on a squashed, idempotent v2.4.0 baseline that adopts existing PHP databases, with polymorphic subscribers registered at build time and a built-in `user` subscribable.
+  2. The `SubscriptionGateway` contract (including `syncPlanToGateway`) has a Stripe implementation. `POST /webhook/stripe/subscriptions` and its legacy alias verify the event, enqueue a job and process it idempotently, and fire the six `golem15.pgsub.*` events.
+  3. The Subscriptions and SubscriptionPlans admin screens, a Go service API, a headless customer API and subscription components in `vue-paymentgateway-layer` are delivered.
+  4. A host test proves checkout, activation, `invoice.paid`, `past_due` with its grace period, cancel and duplicate-event idempotency against a Stripe fake.
+  5. The new code has unit tests, delivered in the phase's last plan.
+
+**Plans:** 0 plans
+
+Plans:
+- [ ] TBD (run /msd-plan-phase 18.1 to break down)
+
 ### Phase 19: Chat and ChatChannels
 
 **Goal:** `Golem15.Chat` and `Golem15.ChatChannels` run on SummerCMS as shared plugins, with realtime delivery through `lighthouse`, ready for the Wavepath port.
@@ -1079,7 +1100,7 @@ Plans:
 ## Progress
 
 **Execution Order:**
-Phases execute in numeric order: 1 → 2 → 3 → 4 → 5 → 6 → 7 → 8 → 9 → 10 → 11 → 12 → 13 → 14 → 14.1 → 14.2 → 14.2.1 → 14.3 → 15 → 16 → 17 → 18 → 19 → 19.1 → 20
+Phases execute in numeric order: 1 → 2 → 3 → 4 → 5 → 6 → 7 → 8 → 9 → 10 → 11 → 12 → 13 → 14 → 14.1 → 14.2 → 14.2.1 → 14.3 → 15 → 16 → 17 → 18 → 18.1 → 19 → 19.1 → 20
 (Phase 2 depends on Phase 1's command kernel; the two are no longer parallel.)
 
 | Phase | Plans Complete | Status | Completed |
@@ -1107,6 +1128,7 @@ Phases execute in numeric order: 1 → 2 → 3 → 4 → 5 → 6 → 7 → 8 →
 | 16. grzybyfunkcjonalne.pl on reusable blog views | 3/5 | In Progress|  |
 | 17. Blog companions | 0/TBD | Not started | - |
 | 18. Payment Gateway | 0/TBD | Not started | - |
+| 18.1. Payment Gateway Subscriptions | 0/TBD | Not started | - |
 | 19. Chat and ChatChannels | 0/TBD | Not started | - |
 | 19.1. Chat satellites | 0/TBD | Not started | - |
 | 20. Płytarium cutover | 0/TBD | Not started | - |

.planning/STATE.md

@@ -8,9 +8,9 @@ stopped_at: Completed 16-03-PLAN.md
 last_updated: "2026-10-09T16:56:24.832Z"
 last_activity: 2026-10-09
 last_activity_desc: Phase 16 execution started
-state_head: 65d577b8285e7119db790b640324917fb180b98e
+state_head: 6ff7d5da3ed237181f347d94f75a5b9877306ad3
 progress:
-  total_phases: 31
+  total_phases: 32
   completed_phases: 13
   total_plans: 148
   completed_plans: 142
@@ -219,6 +219,7 @@ Progress: [██████████] 100%
 - Phase 20 edited: Płytarium production cutover moved here from Phase 15
 - Phase 14.2.1 inserted after Phase 14.2: sm-translate-plugin so Journal can keep translatable fields (URGENT)
 - Phase 14.3 inserted after Phase 14.2.1: One-command app scaffolding: summer new + summercms.io/new bootstrap script; ships as v0.1.13 (URGENT)
+- Phase 18.1 inserted after Phase 18: Payment Gateway Subscriptions (split from Phase 18 per 18-CONTEXT D-01)
 
 ### Decisions