feat(dns-providers): add provider-agnostic DNS provider form metadata and reusable UI for create/edit flows

ts/dns/providers/factory.ts

@@ -9,6 +9,21 @@ import { CloudflareDnsProvider } from './cloudflare.provider.js';
  * Instantiate a runtime DNS provider client from a stored DnsProviderDoc.
  *
  * @throws if the provider type is not supported.
+ *
+ * ## Adding a new provider (e.g. Route53)
+ *
+ * 1. **Type union** — extend `TDnsProviderType` in
+ *    `ts_interfaces/data/dns-provider.ts` (e.g. `'cloudflare' | 'route53'`).
+ * 2. **Credentials interface** — add `IRoute53Credentials` and append it to
+ *    the `TDnsProviderCredentials` discriminated union.
+ * 3. **Descriptor** — append a new entry to `dnsProviderTypeDescriptors` so
+ *    the OpsServer UI picks up the new type and renders the right credential
+ *    form fields automatically.
+ * 4. **Provider class** — create `ts/dns/providers/route53.provider.ts`
+ *    implementing `IDnsProviderClient`.
+ * 5. **Factory case** — add a new `case 'route53':` below. The
+ *    `_exhaustive: never` line will fail to compile until you do.
+ * 6. **Index** — re-export the new class from `ts/dns/providers/index.ts`.
  */
 export function createDnsProvider(
   type: TDnsProviderType,
@@ -24,6 +39,8 @@ export function createDnsProvider(
       return new CloudflareDnsProvider(credentials.apiToken);
     }
     default: {
+      // If you see a TypeScript error here after extending TDnsProviderType,
+      // add a `case` for the new type above. The `never` enforces exhaustiveness.
       const _exhaustive: never = type;
       throw new Error(`createDnsProvider: unsupported provider type: ${_exhaustive}`);
     }