feat(phase2): aircraft market, fleet management, finances, loans

- market.php: Buy new aircraft (6 types: Dash8 to A380)
- aircraft.php: Fleet management, crew assignment, route planning
- finances.php: Account balance, transactions, loans
- Database.php: Extended with loan/transaction/aircraft methods
- schema.sql: Aircraft types table, 10M starting balance, INSERT OR IGNORE
- dashboard.php: Updated with fleet/financial overview
- Fixed: duplicate function declarations in Database.php
- Fixed: initializeSchema() with idempotent error handling

database/schema.sql

@@ -8,7 +8,7 @@ CREATE TABLE IF NOT EXISTS users (
     email VARCHAR(100) UNIQUE NOT NULL,
     password_hash VARCHAR(255) NOT NULL,
     airline_name VARCHAR(100) DEFAULT '',
-    balance DECIMAL(15,2) DEFAULT 500000.00,
+    balance DECIMAL(15,2) DEFAULT 10000000.00,
     level INTEGER DEFAULT 1,
     experience INTEGER DEFAULT 0,
     created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
@@ -92,10 +92,55 @@ CREATE TABLE IF NOT EXISTS daily_stats (
     total_revenue DECIMAL(15,2) DEFAULT 0.00,
     total_profit DECIMAL(15,2) DEFAULT 0.00,
     fuel_cost DECIMAL(15,2) DEFAULT 0.00,
+    maintenance_cost DECIMAL(15,2) DEFAULT 0.00,
     UNIQUE(user_id, date),
     FOREIGN KEY (user_id) REFERENCES users(id)
 );
 
+-- Kredite
+CREATE TABLE IF NOT EXISTS loans (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    user_id INTEGER NOT NULL,
+    principal DECIMAL(15,2) NOT NULL,
+    current_amount DECIMAL(15,2) NOT NULL,
+    interest_rate DECIMAL(5,4) DEFAULT 0.02,
+    daily_interest DECIMAL(15,2) DEFAULT 0.00,
+    days_outstanding INTEGER DEFAULT 0,
+    status VARCHAR(20) DEFAULT 'active',
+    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+    due_date DATE,
+    FOREIGN KEY (user_id) REFERENCES users(id)
+);
+
+-- Transaktionen (alle Buchungen)
+CREATE TABLE IF NOT EXISTS transactions (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    user_id INTEGER NOT NULL,
+    type VARCHAR(50) NOT NULL,
+    category VARCHAR(50) NOT NULL,
+    amount DECIMAL(15,2) NOT NULL,
+    balance_after DECIMAL(15,2) NOT NULL,
+    description TEXT DEFAULT '',
+    reference_id INTEGER,
+    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (user_id) REFERENCES users(id)
+);
+
+-- Wartungshistorie
+CREATE TABLE IF NOT EXISTS maintenance_history (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    aircraft_id INTEGER NOT NULL,
+    user_id INTEGER NOT NULL,
+    maintenance_type VARCHAR(50) DEFAULT 'scheduled',
+    cost DECIMAL(15,2) NOT NULL,
+    condition_before DECIMAL(5,2) DEFAULT 100.00,
+    condition_after DECIMAL(5,2) DEFAULT 100.00,
+    notes TEXT DEFAULT '',
+    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (aircraft_id) REFERENCES aircraft(id),
+    FOREIGN KEY (user_id) REFERENCES users(id)
+);
+
 -- Events (Werbeaktionen, Wettbewerbe)
 CREATE TABLE IF NOT EXISTS events (
     id INTEGER PRIMARY KEY AUTOINCREMENT,
@@ -114,3 +159,27 @@ CREATE INDEX IF NOT EXISTS idx_flights_user ON flights(user_id);
 CREATE INDEX IF NOT EXISTS idx_flights_route ON flights(route_id);
 CREATE INDEX IF NOT EXISTS idx_aircraft_user ON aircraft(user_id);
 CREATE INDEX IF NOT EXISTS idx_airports_iata ON airports(iata_code);
+
+-- Flugzeugtypen (Referenztabelle)
+CREATE TABLE IF NOT EXISTS aircraft_types (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    code VARCHAR(20) UNIQUE NOT NULL,
+    name VARCHAR(100) NOT NULL,
+    manufacturer VARCHAR(50) NOT NULL,
+    range_km INTEGER NOT NULL,
+    capacity INTEGER NOT NULL,
+    buy_price DECIMAL(15,2) NOT NULL,
+    crew_cost_per_tick DECIMAL(10,2) NOT NULL,
+    fuel_per_km DECIMAL(6,4) DEFAULT 0.1500,
+    maintenance_interval INTEGER DEFAULT 50,
+    description TEXT DEFAULT '',
+    created_at DATETIME DEFAULT CURRENT_TIMESTAMP
+);
+
+INSERT OR IGNORE INTO aircraft_types (code, name, manufacturer, range_km, capacity, buy_price, crew_cost_per_tick, fuel_per_km, maintenance_interval, description) VALUES
+('dash8-100', 'Dash 8-100', 'Bombardier', 1500, 37, 500000.00, 200.00, 0.12, 50, 'Kleiner RegionalturboProp mit 37 Sitzen'),
+('atr72-500', 'ATR 72-500', 'ATR', 1650, 70, 1500000.00, 300.00, 0.15, 50, 'Mittlerer RegionalturboProp mit 70 Sitzen'),
+('a320-200', 'A320-200', 'Airbus', 5700, 150, 8000000.00, 600.00, 0.25, 50, 'Kurz-/Mittelstrecken-Jet mit 150 Sitzen'),
+('b737-800', 'B737-800', 'Boeing', 5700, 162, 9500000.00, 650.00, 0.26, 50, 'Kurz-/Mittelstrecken-Jet mit 162 Sitzen'),
+('b777-200', 'B777-200', 'Boeing', 12000, 300, 35000000.00, 1200.00, 0.55, 50, 'Langstrecken-Widebody mit 300 Sitzen'),
+('a380-800', 'A380-800', 'Airbus', 15200, 525, 85000000.00, 2000.00, 0.80, 50, 'Doppelstöckiger Langstrecken-Airliner mit 525 Sitzen');