refactor: break up large functions, add RPG/league/salary/burnout, fix bugs, add tests

- Refactor GenerateMonthlyReport (198→70), HandleCallback (128→85),
  handleHistoryCallback (131→38), handleExportCallback (100→25),
  checkAchievements (86→25) into extracted helper functions
- Add RPG system (XP, levels, streak, achievements, burnout)
- Add WorkTime League leaderboard
- Add salary estimation with configurable currency/rate
- Add input sanitization (SanitizeNote, SanitizeDisplayName)
- Add settings select-style pickers for toggles (report, RPG, league)
- Add break threshold inline picker UI
- Add event notes with pending state and /note command
- Add multi-calendar support (Jalali, Hijri)
- Add Excel export with theme picker
- Fix: getTodayBreakThreshold uses user's timezone (was UTC)
- Fix: acknowledgeCallback passes real callback ID
- Fix: currency symbol safety with currencySymbol() helper
- Fix: count work hours in summary on day-off days
- Fix: unsilence all error returns from SQL Exec/Bot API/migrations
- Remove stale db/schema.sql and unreferenced computeWeekTotals
- Extract constants: DateLayout, TimeLayout, secondsPerHour, etc.
- Add 12 new tests (XP, salary, sanitize, currency, dateutil)
- Remove duplicate package doc comment in totals.go

internal/bot/summary.go

@@ -108,6 +108,14 @@ func (h *Handler) buildMonthlySummary(user *db.User, calY, calM int, startStr, e
 	if totalBreak > 0 {
 		b.WriteString(fmt.Sprintf(", %s break", formatDuration(totalBreak)))
 	}
+
+	st, _ := h.DB.GetOrCreateSettings(user.ID)
+	if st.HourlyRate > 0 {
+		est := computeMonthlySalary(days, h.DB, user.ID, st.HourlyRate, loc)
+		b.WriteString(fmt.Sprintf("\nSalary: %s (%.1f hours, %d days)",
+			est.formatSalary(st.Currency), est.WorkHours, est.WorkDays))
+	}
+
 	b.WriteString("\n\nDetails:\n")
 	for _, d := range dayDetails {
 		b.WriteString(d)
@@ -115,39 +123,3 @@ func (h *Handler) buildMonthlySummary(user *db.User, calY, calM int, startStr, e
 	}
 	return b.String()
 }
-
-// computeWeekTotals returns the total work seconds for the current week (Mon-Sun containing today).
-func (h *Handler) computeWeekTotals(user *db.User, loc *time.Location) int64 {
-	now := time.Now().In(loc)
-	weekday := now.Weekday()
-	if weekday == time.Sunday {
-		weekday = 7
-	}
-	monday := now.AddDate(0, 0, -int(weekday-time.Monday))
-	sunday := monday.AddDate(0, 0, 6)
-
-	startStr := monday.Format("2006-01-02")
-	endStr := sunday.Format("2006-01-02")
-
-	days, err := h.DB.GetUserDaysInRange(user.ID, startStr, endStr)
-	if err != nil {
-		return 0
-	}
-
-	var total int64
-	for _, day := range days {
-		if day.IsDayOff {
-			continue
-		}
-		events, err := h.DB.EventsForDayByDayID(day.ID)
-		if err != nil || len(events) == 0 {
-			continue
-		}
-		y, m, d := parseGregorianDateKey(day.Date)
-		dayStart := time.Date(y, time.Month(m), d, 0, 0, 0, 0, loc).Unix()
-		dayEnd := time.Date(y, time.Month(m), d, 23, 59, 59, 0, loc).Unix()
-		totals := ComputeDailyTotals(events, day.MinBreakThreshold, dayStart, dayEnd)
-		total += totals.TotalSeconds
-	}
-	return total
-}