Phase 6: schedules, blocklists, allowlists (editors + effective state)

- Weekly schedule editor per device: a Monday-Sunday grid of blocking
  windows, including windows that cross midnight.
- Blocklist/allowlist editor per device: app (Android package / Windows
  process) and site (hostname) entries, tagged by the device platform.
- Effective desired state: a manual lock, an active schedule window, or
  neither. While blocked the allowlist is honoured (Spotify stays while
  other apps are blocked). Published retained with reason schedule/manual.
- Boundary-aware republish loop so a window turns on and off on time,
  and manual lock expiry is cleared promptly.
- CONTROL_TIMEZONE (default Australia/Sydney) with embedded tzdata, so
  wall-clock windows are evaluated in the family zone, not the container.
- Every change is written to the append-only audit log (FR-15).

Co-Authored-By: Paperclip <noreply@paperclip.ing>

internal/config/config.go

@@ -11,6 +11,9 @@ import (
 	"strconv"
 	"strings"
 	"time"
+	// Embed the IANA time zone database so CONTROL_TIMEZONE resolves even in a
+	// container without tzdata, such as the test image.
+	_ "time/tzdata"
 )
 
 // Config is the fully resolved runtime configuration.
@@ -37,6 +40,11 @@ type Config struct {
 	AppEnv string
 	// Version is injected at build time.
 	Version string
+	// ScheduleLocation is the timezone weekly schedule windows are evaluated in
+	// (CONTROL_TIMEZONE). Windows are wall-clock, so this must be the family's
+	// zone, not the container's default of UTC. It defaults to
+	// DefaultTimezone.
+	ScheduleLocation *time.Location
 
 	// MQTTEnabled turns the broker link on. When false the service runs
 	// HTTP-only and never touches the broker.
@@ -102,6 +110,12 @@ func Load() (*Config, error) {
 	}
 	cfg.LogLevel = lvl
 
+	loc, err := time.LoadLocation(env("CONTROL_TIMEZONE", DefaultTimezone))
+	if err != nil {
+		return nil, fmt.Errorf("CONTROL_TIMEZONE: %w", err)
+	}
+	cfg.ScheduleLocation = loc
+
 	if err := cfg.validateMQTT(); err != nil {
 		return nil, err
 	}
@@ -114,6 +128,10 @@ func Load() (*Config, error) {
 // to the host gateway.
 const DefaultMQTTBroker = "tcp://host.docker.internal:1883"
 
+// DefaultTimezone is the schedule timezone used when CONTROL_TIMEZONE is unset.
+// It matches the lab host's configured zone; set CONTROL_TIMEZONE to override.
+const DefaultTimezone = "Australia/Sydney"
+
 // MQTTTLS reports whether the broker URL asks for TLS.
 func (c *Config) MQTTTLS() bool {
 	return strings.HasPrefix(c.MQTTBroker, "tls://") || strings.HasPrefix(c.MQTTBroker, "ssl://")