fix: resolve go vet error and dayStart logic in ComputeDailyTotals

- Fix 'string(d)' int-to-rune conversion in rpg_test.go by using fmt.Sprintf
- Fix ComputeDailyTotals dayStart logic: initial state should be StateWorking
  when dayStart > 0, correctly counting work from dayStart to first out event
- Update README project structure to reflect new domain/handler/repo layout
- Implement missing achievements: rpg_pioneer (on RPG enable) and
  salary_setter (on first rate set)
- Add tryUnlockAchievement helper to Handler

README.md

@@ -147,24 +147,35 @@ Four color themes are available in settings: **Ocean**, **Beach**, **Rose**, **C
 │   ├── main.go              Entrypoint, polling/webhook, scheduler
 │   └── webhook.go           Webhook mode with TLS support
 ├── internal/
-│   ├── bot/
-│   │   ├── handlers.go      Message/callback routing, views, menu builders
-│   │   ├── clock.go         Clock in/out, day off, report
+│   ├── domain/              Pure business logic, no external dependencies
+│   │   ├── types.go         Core domain types (User, Event, Day, RPGStats, ...)
+│   │   ├── constants.go     App-wide constants and thresholds
+│   │   ├── dateutil.go      Gregorian/Jalali/Hijri calendar conversions
 │   │   ├── totals.go        Break/work computation state machine
+│   │   ├── rpg.go           XP curves, levels, streaks
+│   │   ├── burnout.go       Burnout trend computation
+│   │   ├── salary.go        Salary estimation, currency helpers
+│   │   └── sanitize.go      Input sanitization helpers
+│   ├── handler/             Telegram bot handlers (one per feature)
+│   │   ├── handler.go       Core handler, routing, helpers
+│   │   ├── clock.go         Clock in/out, day off, report
 │   │   ├── calendar.go      History view and inline event editing
 │   │   ├── export.go        Excel (.xlsx) report generation
-│   │   ├── dateutil.go      Gregorian/Jalali/Hijri conversions & calendars
-│   │   ├── rpg.go           XP, levels, streaks, achievements
+│   │   ├── rpg.go           RPG stats, achievements, aggregates
 │   │   ├── league.go        WorkTime League leaderboard
-│   │   ├── salary.go        Salary estimation, rate/currency commands
-│   │   ├── burnout.go       Burnout assessment model
+│   │   ├── salary.go        Salary estimation view
+│   │   ├── burnout.go       Burnout assessment view
 │   │   ├── settings.go      Settings menu with inline pickers
 │   │   ├── summary.go       Monthly summary
-│   │   ├── report.go        Daily report builder
-│   │   └── sanitize.go      Input sanitization helpers
-│   └── db/
-│       ├── store.go         SQLite store (data access layer)
-│       └── migrations/      Goose-managed SQL migrations
+│   │   ├── report.go        Daily report builder, status text
+│   │   ├── note.go          Note command, edit command
+│   │   ├── worktype.go      Work type selection
+│   │   └── keyboard.go      Inline keyboard builders
+│   └── repo/                Data access layer
+│       ├── interface.go     Repository interface
+│       ├── store.go         SQLite implementation
+│       └── migrations.go    Goose-managed migration runner
+│       └── migrations/      SQL migration files
 │           ├── 001_init.sql Initial schema
 │           └── 002_features.sql RPG, achievements, user_settings
 ├── .gitea/workflows/