Turn the status page into a full status page generator

Components can be put in groups and given public names. Public incidents carry
posts written for customers (the internal timeline stays internal), the
components they affect, and a page for each incident plus paged history.
Scheduled maintenance has its own window, shows affected components as under
maintenance, and is announced when scheduled, started, ended or canceled.

Branding (title, logo, accent checked for contrast, contact link, footer) and a
custom domain that serves only the status page. Visitors follow by RSS, by
confirmed email, or by webhook that must answer a test request. Admin UI for
all of it, tests, README and design notes.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

internal/sandbar/monitor.go

@@ -30,15 +30,17 @@ type Monitor struct {
 	Target       string `json:"target"` // URL, host:port, hostname, or host[:port] for tls
 	IntervalS    int    `json:"intervalS"`
 	TimeoutS     int    `json:"timeoutS"`
-	Retries      int    `json:"retries"`  // failures in a row before it is down (default 2)
-	Expect       string `json:"expect"`   // http: accepted status, e.g. "200-299" (default)
-	Keyword      string `json:"keyword"`  // http: text the body must contain
-	WarnDays     int    `json:"warnDays"` // tls: fail when the certificate expires within this many days (default 14)
-	GraceS       int    `json:"graceS"`   // heartbeat: extra time allowed past the interval
-	Token        string `json:"token"`    // heartbeat: the secret in the ping URL
-	PolicyID     string `json:"policyId"` // escalation policy for the alert it raises
-	Severity     string `json:"severity"` // alert severity (default critical)
-	Public       bool   `json:"public"`   // shown on the status page
+	Retries      int    `json:"retries"`    // failures in a row before it is down (default 2)
+	Expect       string `json:"expect"`     // http: accepted status, e.g. "200-299" (default)
+	Keyword      string `json:"keyword"`    // http: text the body must contain
+	WarnDays     int    `json:"warnDays"`   // tls: fail when the certificate expires within this many days (default 14)
+	GraceS       int    `json:"graceS"`     // heartbeat: extra time allowed past the interval
+	Token        string `json:"token"`      // heartbeat: the secret in the ping URL
+	PolicyID     string `json:"policyId"`   // escalation policy for the alert it raises
+	Severity     string `json:"severity"`   // alert severity (default critical)
+	Public       bool   `json:"public"`     // shown on the status page
+	Group        string `json:"group"`      // status page component group id; empty for none
+	PublicName   string `json:"publicName"` // name on the status page; empty to use Name
 	AllowPrivate bool   `json:"allowPrivate"`
 	Enabled      bool   `json:"enabled"`
 }