feat: SolaceNet gateway rails, IRU marketplace hardening, and docs

- Gateway adapter registry, rails routes, optional SOLACENET_GATEWAY_RAILS_ENFORCE; HTTP integration tests.
- IRU marketplace: rate limits, public routes, notifications/SMTP env docs; marketplace UI constants and flows.
- Quantum proxy legacy protocol types; debank/tezos/GSDS touch-ups; .env.example operator notes.
- SolaceNet doc set (gaps, runbooks, telecom schema example).

Tests: npm run test:iru-marketplace, npm run test:gateway (pass).
Note: full-repo tsc still reports unrelated legacy errors outside this change set.
Made-with: Cursor

docs/solacenet/schemas/telecom-northbound-event.example.json

@@ -0,0 +1,27 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://dbis.example/schemas/solacenet/telecom-northbound-event.example.json",
+  "title": "Telecom boundary → Core northbound event (example)",
+  "description": "Placeholder contract for PG-QP-003 when a carrier boundary service exists. Not wire format for SS7; JSON over HTTPS/Kafka from the boundary only.",
+  "type": "object",
+  "required": ["eventId", "eventType", "occurredAt", "correlationId", "tenantId"],
+  "properties": {
+    "eventId": { "type": "string", "format": "uuid" },
+    "eventType": {
+      "type": "string",
+      "examples": ["carrier.signaling.observed", "carrier.route.health", "carrier.fraud.signal"]
+    },
+    "occurredAt": { "type": "string", "format": "date-time" },
+    "correlationId": { "type": "string" },
+    "tenantId": { "type": "string" },
+    "programId": { "type": "string" },
+    "region": { "type": "string" },
+    "channel": { "type": "string", "const": "TELECOM_NORTHBOUND" },
+    "payload": {
+      "type": "object",
+      "additionalProperties": true,
+      "description": "Opaque carrier-normalized facts; no raw MAP/CAP on this bus."
+    }
+  },
+  "additionalProperties": false
+}