Add pricing system with tiers, seasons, and calculator (v0.2.0)

- Create PricingTier enum for short/mid/long-term pricing
- Add Season class for seasonal pricing with date ranges
- Implement Calculator for price calculations with breakdown
- Add pricing meta box to Room post type
- Create Seasons admin page for managing seasonal pricing
- Add Pricing settings tab with tier thresholds
- Support weekend surcharges and configurable weekend days
- Add price column to room list admin

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

PLAN.md

@@ -38,26 +38,26 @@ This document outlines the implementation plan for the WP BnB Management plugin.
   - WiFi, Parking, Breakfast, etc.
   - Non-hierarchical (tags)
 
-## Phase 2: Pricing System (v0.2.0)
+## Phase 2: Pricing System (v0.2.0) - Complete
 
 ### Pricing Classes
 
-- [ ] Short-term pricing (per night, 1-6 nights)
-- [ ] Mid-term pricing (per week, 1-4 weeks)
-- [ ] Long-term pricing (per month, 1+ months)
+- [x] Short-term pricing (per night, 1-6 nights)
+- [x] Mid-term pricing (per week, 1-4 weeks)
+- [x] Long-term pricing (per month, 1+ months)
 
 ### Price Configuration
 
-- [ ] Room-level price settings
-- [ ] Seasonal pricing periods
-- [ ] Weekend/weekday differentiation
-- [ ] Currency formatting and display
+- [x] Room-level price settings
+- [x] Seasonal pricing periods
+- [x] Weekend/weekday differentiation
+- [x] Currency formatting and display
 
 ### Price Calculation
 
-- [ ] Automatic tier detection based on duration
-- [ ] Price breakdown display
-- [ ] Discount handling
+- [x] Automatic tier detection based on duration
+- [x] Price breakdown display
+- [x] Discount handling (via seasonal modifiers)
 
 ## Phase 3: Booking System (v0.3.0)
 
@@ -289,7 +289,7 @@ The plugin will provide extensive hooks for customization:
 | ------- | --------------- | -------- |
 | 0.0.1   | Initial setup   | Complete |
 | 0.1.0   | Data structures | Complete |
-| 0.2.0   | Pricing         | TBD      |
+| 0.2.0   | Pricing         | Complete |
 | 0.3.0   | Bookings        | TBD      |
 | 0.4.0   | Guests          | TBD      |
 | 0.5.0   | Services        | TBD      |