A forgotten password is set through a one-time link

/forgot mails a link to set a new password when the cluster's mail settings
say how - SMTP relay, sender, and the public base_url the link points at,
never the request's Host - and says the same whether or not the address has
an account. /reset sets it once, closing every session. Links are kept by
their hash in password_resets, good for an hour, a newer one replacing an
older. Without mail, /forgot says to ask an operator, and llmgw users
reset-link makes the link to hand over. Single sign-on accounts get none.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

docs/reference.md

@@ -289,6 +289,7 @@ rather than repeated.
 | `guard` | `guard.Config` | [Server](#server) |
 | `secrets` | `Secrets` | [Server](#server) |
 | `notify` | `notify.Config` | [Server](#server) |
+| `mail` | `mail.Config` | [Server](#server) |
 | `firewall` | `FirewallSettings` | [Server](#server) |
 | `firewall_networks` | `[]string` | [Server](#server) |
 | `backup_recipients` | `[]string` | [Server](#server) |
@@ -376,6 +377,11 @@ rather than repeated.
 | `enabled` | `*bool` | [guard.Config](#guardconfig) |
 | `default` | `[]string` | [guard.Config](#guardconfig) |
 | `policies` | `map[string]Policy` | [guard.Config](#guardconfig) |
+| `smtp` | `string` | [mail.Config](#mailconfig) |
+| `from` | `string` | [mail.Config](#mailconfig) |
+| `username` | `string` | [mail.Config](#mailconfig) |
+| `password_file` | `string` | [mail.Config](#mailconfig) |
+| `base_url` | `string` | [mail.Config](#mailconfig) |
 | `webhooks` | `[]Webhook` | [notify.Config](#notifyconfig) |
 | `host` | `string` | [notify.Config](#notifyconfig) |
 | `work_dir` | `string` | [supervisor.Config](#supervisorconfig) |
@@ -2466,6 +2472,15 @@ Prometheus and Alertmanager in between. Empty sends nothing.
 
 Takes a [notify.Config](#notifyconfig) block.
 
+### `mail`
+
+`mail.Config`
+
+Mail is where the gateway's few emails go out from: a link to set a
+forgotten password. Unset, none is sent and people ask an operator.
+
+Takes a [mail.Config](#mailconfig) block.
+
 ### `firewall`
 
 `FirewallSettings`
@@ -3092,6 +3107,40 @@ whatever is defined or attached. Unset is on.
 
 `map[string]Policy`
 
+## mail.Config
+
+### `smtp`
+
+`string`
+
+SMTP is the relay, host:port: 587 with STARTTLS, 465 with TLS from the
+start, 25 as the relay allows. Empty sends nothing.
+
+### `from`
+
+`string`
+
+From is the sender, llmgw@example.com or "llmgw <llmgw@example.com>".
+
+### `username`
+
+`string`
+
+Username and PasswordFile log in to the relay, when it wants that.
+The password is a secret reference: a file, env:NAME or vault:path.
+
+### `password_file`
+
+`string`
+
+### `base_url`
+
+`string`
+
+BaseURL is the gateway's public address, which links in mail point
+at: https://llm.example.com. Never taken from a request, whose Host a
+sender chooses and could point a reset link at their own site.
+
 ## notify.Config
 
 ### `webhooks`