Implement urgency system with TaskWarrior-inspired calculation

- Add urgency calculation based on multiple factors:
  * Due date (linear scale: overdue=12.0, today=10.0, week=6.0, 2weeks=2.0)
  * Priority (H=6.0, M=3.9, D=1.8, L=0.0)
  * Age (0-2.0 over 365 days)
  * Active status (+4.0 boost)
  * Waiting status (-3.0 penalty)
  * Tags (+1.0 with count modifier)
  * Project assignment (+1.0)
  * Configurable urgent tag (default 'next', +15.0)

- Replace priority column with urgency in all reports
  * Display as decimal with 1 decimal place
  * 4-tier color coding: ≥10 (bright red), ≥5 (red), ≥2 (yellow), <2 (cyan)
  * Minimal format color-coded by urgency

- Add default urgency sorting to all reports
  * list, minimal, active, ready, overdue reports sort by urgency
  * newest/oldest keep date-based sorting

- Implement 'next' report
  * Shows most urgent ready tasks
  * Configurable limit (default 5)
  * Only includes tasks ready to work on (no future wait/scheduled)

- Add urgency display to info command
  * Shows urgency score alongside priority

- All urgency coefficients configurable via config
  * Adjusted defaults for Opal's simpler model (no blocking/annotations)
  * Configurable urgent tag name (not hardcoded to 'next')

Priority order maintained: High > Medium > Default > Low

opal-task/internal/engine/config.go

@@ -18,6 +18,22 @@ type Config struct {
 	WeekStartDay   string `mapstructure:"week_start_day"`
 	DefaultDueTime string `mapstructure:"default_due_time"`
 
+	// Urgency coefficients
+	UrgencyDue         float64 `mapstructure:"urgency_due_coefficient"`
+	UrgencyPriorityH   float64 `mapstructure:"urgency_priority_h_coefficient"`
+	UrgencyPriorityM   float64 `mapstructure:"urgency_priority_m_coefficient"`
+	UrgencyPriorityD   float64 `mapstructure:"urgency_priority_d_coefficient"`
+	UrgencyPriorityL   float64 `mapstructure:"urgency_priority_l_coefficient"`
+	UrgencyActive      float64 `mapstructure:"urgency_active_coefficient"`
+	UrgencyAge         float64 `mapstructure:"urgency_age_coefficient"`
+	UrgencyAgeMax      int     `mapstructure:"urgency_age_max"`
+	UrgencyTags        float64 `mapstructure:"urgency_tags_coefficient"`
+	UrgencyProject     float64 `mapstructure:"urgency_project_coefficient"`
+	UrgencyWaiting     float64 `mapstructure:"urgency_waiting_coefficient"`
+	UrgencyUrgentTag   string  `mapstructure:"urgency_urgent_tag"`
+	UrgencyUrgentCoeff float64 `mapstructure:"urgency_urgent_coefficient"`
+	NextLimit          int     `mapstructure:"next_limit"`
+
 	// Sync settings
 	SyncEnabled      bool   `mapstructure:"sync_enabled"`
 	SyncURL          string `mapstructure:"sync_url"`
@@ -89,6 +105,22 @@ func LoadConfig() (*Config, error) {
 	v.SetDefault("week_start_day", "monday")
 	v.SetDefault("default_due_time", "")
 
+	// Urgency defaults (adjusted for Opal's simpler model)
+	v.SetDefault("urgency_due_coefficient", 12.0)
+	v.SetDefault("urgency_priority_h_coefficient", 6.0)
+	v.SetDefault("urgency_priority_m_coefficient", 3.9)
+	v.SetDefault("urgency_priority_d_coefficient", 1.8)
+	v.SetDefault("urgency_priority_l_coefficient", 0.0)
+	v.SetDefault("urgency_active_coefficient", 4.0)
+	v.SetDefault("urgency_age_coefficient", 2.0)
+	v.SetDefault("urgency_age_max", 365)
+	v.SetDefault("urgency_tags_coefficient", 1.0)
+	v.SetDefault("urgency_project_coefficient", 1.0)
+	v.SetDefault("urgency_waiting_coefficient", -3.0)
+	v.SetDefault("urgency_urgent_tag", "next")
+	v.SetDefault("urgency_urgent_coefficient", 15.0)
+	v.SetDefault("next_limit", 5)
+
 	// Sync defaults
 	v.SetDefault("sync_enabled", false)
 	v.SetDefault("sync_url", "")
@@ -138,6 +170,22 @@ func SaveConfig(cfg *Config) error {
 	v.Set("week_start_day", cfg.WeekStartDay)
 	v.Set("default_due_time", cfg.DefaultDueTime)
 
+	// Urgency settings
+	v.Set("urgency_due_coefficient", cfg.UrgencyDue)
+	v.Set("urgency_priority_h_coefficient", cfg.UrgencyPriorityH)
+	v.Set("urgency_priority_m_coefficient", cfg.UrgencyPriorityM)
+	v.Set("urgency_priority_d_coefficient", cfg.UrgencyPriorityD)
+	v.Set("urgency_priority_l_coefficient", cfg.UrgencyPriorityL)
+	v.Set("urgency_active_coefficient", cfg.UrgencyActive)
+	v.Set("urgency_age_coefficient", cfg.UrgencyAge)
+	v.Set("urgency_age_max", cfg.UrgencyAgeMax)
+	v.Set("urgency_tags_coefficient", cfg.UrgencyTags)
+	v.Set("urgency_project_coefficient", cfg.UrgencyProject)
+	v.Set("urgency_waiting_coefficient", cfg.UrgencyWaiting)
+	v.Set("urgency_urgent_tag", cfg.UrgencyUrgentTag)
+	v.Set("urgency_urgent_coefficient", cfg.UrgencyUrgentCoeff)
+	v.Set("next_limit", cfg.NextLimit)
+
 	// Sync settings
 	v.Set("sync_enabled", cfg.SyncEnabled)
 	v.Set("sync_url", cfg.SyncURL)