Add trip mode: self-learning EV charging scheduler

User enters car SOC + departure deadline; EMS computes when to start
charging and activates the wallbox at the right time (grid import OK
for trip mode). Charging rate is learned from completed PM sessions,
improving over time. Car profiles (Mini Cooper SE 50 kWh, BMW ix2 63
kWh) are config-driven and selectable per trip.

- internal/trip/trip.go: Goal/Session types, Manager with per-cycle
  Tick() that accumulates energy, detects session completion, learns
  avg charge rate from JSONL session log
- internal/config: CarProfile + Cars map, TripGoalFile, SessionLogFile
- internal/status: trip card (active goal) + trip form (set new goal),
  CarOption list, formatDay/formatDur helpers
- main.go: tripMgr lifecycle, /trip + /trip/cancel HTTP handlers,
  runCycle integration (ShouldStartNow → ApplyOverride, auto-clear)
- configs/ems-config.yaml: cars section, trip_goal_file, session_log_file

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/config/config.go

@@ -10,17 +10,24 @@ import (
 
 // Config is the top-level EMS configuration.
 type Config struct {
-	Prometheus PrometheusConfig  `yaml:"prometheus"`
-	Shelly     ShellyConfig      `yaml:"shelly"`
-	Viessmann  ViessmannConfig   `yaml:"viessmann"`
-	SOC        SOCThresholds     `yaml:"soc_thresholds"`
-	Hysteresis HysteresisConfig  `yaml:"hysteresis"`
-	Thresholds PowerThresholds   `yaml:"thresholds"`
-	Consumers  ConsumersConfig   `yaml:"consumers"`
-	Strategic  StrategicConfig   `yaml:"strategic"`
-	Season     SeasonConfig      `yaml:"season"`
-	Forecast   ForecastConfig    `yaml:"forecast"`
-	EMS        EMSConfig         `yaml:"ems"`
+	Prometheus PrometheusConfig      `yaml:"prometheus"`
+	Shelly     ShellyConfig          `yaml:"shelly"`
+	Viessmann  ViessmannConfig       `yaml:"viessmann"`
+	SOC        SOCThresholds         `yaml:"soc_thresholds"`
+	Hysteresis HysteresisConfig      `yaml:"hysteresis"`
+	Thresholds PowerThresholds       `yaml:"thresholds"`
+	Consumers  ConsumersConfig       `yaml:"consumers"`
+	Strategic  StrategicConfig       `yaml:"strategic"`
+	Season     SeasonConfig          `yaml:"season"`
+	Forecast   ForecastConfig        `yaml:"forecast"`
+	Cars       map[string]CarProfile `yaml:"cars"`
+	EMS        EMSConfig             `yaml:"ems"`
+}
+
+// CarProfile holds the display name and battery capacity of a known vehicle.
+type CarProfile struct {
+	Name       string  `yaml:"name"`
+	BatteryKWh float64 `yaml:"battery_kwh"`
 }
 
 // PrometheusConfig holds Prometheus connection settings.
@@ -160,6 +167,8 @@ type EMSConfig struct {
 	OverrideTimeout    string  `yaml:"override_timeout"`
 	OverrideMaxImportW float64 `yaml:"override_max_import_w"` // cancel override if grid import exceeds this (0 = disabled)
 	MonitorOnlyFile    string  `yaml:"monitor_only_file"`     // flag file path: presence = monitor-only mode active
+	TripGoalFile       string  `yaml:"trip_goal_file"`        // persisted active trip goal
+	SessionLogFile     string  `yaml:"session_log_file"`      // JSONL log of completed charge sessions
 }
 
 func (e *EMSConfig) PollIntervalParsed() time.Duration {