feature: service accounts have a display name and a description, which the router sets for its internal ones.

README.md

@@ -393,9 +393,10 @@ is switched on:
   `account` for a Manager-only account (see Managing users);
 - the package's own schema, `cn=vpn-router,cn=schema,cn=config`, under the OID
   `2.25.98477352595735834532404256531620013001` of the UUID arc: the auxiliary class
-  `vpnRouterAccount` with `MAY ( mail $ vpnRouterScope )`, which Manager-only and service accounts
-  have, and the attribute `vpnRouterScope`, authorization scopes, of which `service` marks a
-  service account;
+  `vpnRouterAccount` with `MAY ( mail $ vpnRouterScope $ displayName $ description )`, which
+  Manager-only and service accounts have, and the attribute `vpnRouterScope`, authorization
+  scopes, of which `service` marks a service account; `displayName` and `description` are the
+  display name and the description of a service account;
 - `ou=groups` holds one `groupOfNames` per group, named by `cn`, with its members' DNs in
   `member` and an optional `description`;
 - `cn=user-manager,ou=services` is the account that changes users and groups; it may write
@@ -429,10 +430,12 @@ it is added:
   the router. `add` without the first and the last name adds one; its names cannot be set later;
 - a service account, a Manager-only account whose `vpnRouterScope` is `service`, which another
   system signs in with to use a router service, such as an OpenTelemetry Collector reading
-  `/metrics`; it cannot sign in to `/auth`. `add --service` adds one, and the web service manages
-  them at `/service-accounts`, not at `/users`. Internal service accounts are those the router
-  creates and manages for its own services; at present that is the metrics service's, the account
-  `metrics.service_account` names while metrics are enabled (see Metrics). The API only lists
+  `/metrics`; it cannot sign in to `/auth`. Besides its name, it has a display name and a
+  description. `add --service` adds one, and the web service manages them at `/service-accounts`,
+  not at `/users`. Internal service accounts are those the router creates and manages for its own
+  services, display name and description included; at present that is the metrics service's, the
+  account `metrics.service_account` names while metrics are enabled (see Metrics), which
+  `vpn-router-setup` names Metrics. The API only lists
   them: `/service-accounts` refuses every other request on one, and `/groups` refuses to put one
   in or take one out of a group, with 403.
 
@@ -466,8 +469,9 @@ vpn-router-user otp-remove alice
 | `list` | The users with their kind, names and e-mail addresses, whether each is enabled or locked, has a certificate and is enrolled for TOTP |
 | `add <name> --first-name F --last-name L --email E` | Adds a VPN user and issues the certificate |
 | `add <name> [--email E]` | Adds a Manager-only account, with the e-mail address when given; one name without the other two options is refused |
-| `add <name> --service [--email E]` | Adds a service account, with the e-mail address when given; the names are refused |
+| `add <name> --service [--display-name N] [--description D] [--email E]` | Adds a service account, with its display name, description and e-mail address when given; the names are refused |
 | `update <name> [--first-name F] [--last-name L] [--email E]` | Changes the names or the e-mail address |
+| `update <name> [--display-name N] [--description D] [--email E]` | Changes the display name, the description or the e-mail address of a service account; `''` removes one |
 | `passwd <name>` | Sets the password |
 | `disable <name>`, `enable <name>` | Locks the user out of OpenVPN and `/auth`, and lets the user in again |
 | `unlock <name>` | Ends a lockout after failed logins and clears the failure count; a disabled user stays disabled |
@@ -752,18 +756,19 @@ curl -H "Authorization: Bearer $TOKEN" -H 'Content-Type: application/json' \
 
 | Request | Body | Answer |
 | --- | --- | --- |
-| `GET /service-accounts` | | `{"service_accounts": [{"name", "internal", "enabled", "locked", "email", ...}, ...]}`, each as `/users` shows a user |
-| `POST /service-accounts` | `{"name", "password", "email"?}` | 201 and the account |
-| `PUT /service-accounts/<name>` | `{"email"}`; `""` removes it | the account |
+| `GET /service-accounts` | | `{"service_accounts": [{"name", "display_name", "description", "internal", "enabled", "locked", "email", ...}, ...]}`, each as `/users` shows a user |
+| `POST /service-accounts` | `{"name", "password", "display_name"?, "description"?, "email"?}` | 201 and the account |
+| `PUT /service-accounts/<name>` | any of `{"display_name", "description", "email"}`; `""` removes one | the account |
 | `PUT /service-accounts/<name>/password` | `{"password": ...}` | the account |
 | `POST /service-accounts/<name>/disable` | | the account |
 | `POST /service-accounts/<name>/enable` | | the account |
 | `POST /service-accounts/<name>/unlock` | | the account |
 | `DELETE /service-accounts/<name>` | | `{"name", "removed": true}` |
 
-The internal service accounts, `internal` true, are only listed: every other request on one gets
-403, as the router manages them. A failure is otherwise as for `/users`, with 404 also for a
-name that is not a service account.
+A display name has at most 64 printable characters and a description at most 256. The internal
+service accounts, `internal` true, are only listed: every other request on one gets 403, as the
+router manages them, their display name and description included. A failure is otherwise as for
+`/users`, with 404 also for a name that is not a service account.
 
 ### The /account API