Implement cross-club friendly match concept with invitations and shared matches

- Added controllers for handling friendly match invitations and shared matches.
- Created migration scripts for `friendly_match_invitation` and `friendly_match_shared` tables.
- Developed models for `FriendlyMatchInvitation` and `FriendlyMatchShared`.
- Established routes for managing invitations and shared matches.
- Implemented services for business logic related to invitations and shared matches.
- Documented the concept plan for the new feature including API endpoints and data models.

backend/migrations/20260530_create_friendly_match_shared_and_invitation.sql

@@ -0,0 +1,84 @@
+-- Manual migration for cross-club friendly match concept
+-- Created: 2026-05-30
+
+-- 1) Invitation table
+CREATE TABLE IF NOT EXISTS `friendly_match_invitation` (
+  `id` INT NOT NULL AUTO_INCREMENT,
+  `from_club_id` INT NOT NULL,
+  `to_club_id` INT NOT NULL,
+  `proposed_date` DATE NOT NULL,
+  `proposed_start_time` TIME NULL,
+  `proposed_match_name` VARCHAR(255) NOT NULL,
+  `message` TEXT NULL,
+  `status` VARCHAR(32) NOT NULL DEFAULT 'pending',
+  `created_by_user_id` INT NULL,
+  `accepted_by_user_id` INT NULL,
+  `accepted_at` DATETIME NULL,
+  `created_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  `updated_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+  PRIMARY KEY (`id`),
+  CONSTRAINT `chk_friendly_match_invitation_clubs_different`
+    CHECK (`from_club_id` <> `to_club_id`),
+  CONSTRAINT `fk_friendly_match_invitation_from_club`
+    FOREIGN KEY (`from_club_id`) REFERENCES `clubs` (`id`) ON DELETE CASCADE,
+  CONSTRAINT `fk_friendly_match_invitation_to_club`
+    FOREIGN KEY (`to_club_id`) REFERENCES `clubs` (`id`) ON DELETE CASCADE,
+  CONSTRAINT `fk_friendly_match_invitation_created_by`
+    FOREIGN KEY (`created_by_user_id`) REFERENCES `user` (`id`) ON DELETE SET NULL,
+  CONSTRAINT `fk_friendly_match_invitation_accepted_by`
+    FOREIGN KEY (`accepted_by_user_id`) REFERENCES `user` (`id`) ON DELETE SET NULL,
+  KEY `idx_friendly_match_invitation_to_status_date` (`to_club_id`, `status`, `proposed_date`),
+  KEY `idx_friendly_match_invitation_from_status_date` (`from_club_id`, `status`, `proposed_date`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+-- 2) Shared match table
+CREATE TABLE IF NOT EXISTS `friendly_match_shared` (
+  `id` INT NOT NULL AUTO_INCREMENT,
+  `home_club_id` INT NOT NULL,
+  `guest_club_id` INT NOT NULL,
+  `date` DATE NOT NULL,
+  `start_time` TIME NULL,
+  `match_name` VARCHAR(255) NULL,
+  `home_team_name` VARCHAR(255) NOT NULL,
+  `guest_team_name` VARCHAR(255) NOT NULL,
+  `location_name` VARCHAR(255) NULL,
+  `location_address` VARCHAR(255) NULL,
+  `location_city` VARCHAR(255) NULL,
+  `location_zip` VARCHAR(32) NULL,
+  `match_system` VARCHAR(120) NOT NULL DEFAULT 'Braunschweiger System',
+  `singles_count` INT NOT NULL DEFAULT 12,
+  `doubles_count` INT NOT NULL DEFAULT 4,
+  `winning_sets` INT NOT NULL DEFAULT 3,
+  `home_match_points` INT NOT NULL DEFAULT 0,
+  `guest_match_points` INT NOT NULL DEFAULT 0,
+  `is_completed` TINYINT(1) NOT NULL DEFAULT 0,
+  `home_participants` JSON NULL,
+  `guest_participants` JSON NULL,
+  `result_details` JSON NULL,
+  `players_ready` JSON NULL,
+  `players_planned` JSON NULL,
+  `players_played` JSON NULL,
+  `status` VARCHAR(32) NOT NULL DEFAULT 'active',
+  `created_by_user_id` INT NULL,
+  `created_from_invitation_id` INT NULL,
+  `created_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  `updated_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+  PRIMARY KEY (`id`),
+  CONSTRAINT `chk_friendly_match_shared_clubs_different`
+    CHECK (`home_club_id` <> `guest_club_id`),
+  CONSTRAINT `fk_friendly_match_shared_home_club`
+    FOREIGN KEY (`home_club_id`) REFERENCES `clubs` (`id`) ON DELETE CASCADE,
+  CONSTRAINT `fk_friendly_match_shared_guest_club`
+    FOREIGN KEY (`guest_club_id`) REFERENCES `clubs` (`id`) ON DELETE CASCADE,
+  CONSTRAINT `fk_friendly_match_shared_created_by`
+    FOREIGN KEY (`created_by_user_id`) REFERENCES `user` (`id`) ON DELETE SET NULL,
+  CONSTRAINT `fk_friendly_match_shared_from_invitation`
+    FOREIGN KEY (`created_from_invitation_id`) REFERENCES `friendly_match_invitation` (`id`) ON DELETE SET NULL,
+  KEY `idx_friendly_match_shared_home_date_time` (`home_club_id`, `date`, `start_time`),
+  KEY `idx_friendly_match_shared_guest_date_time` (`guest_club_id`, `date`, `start_time`),
+  KEY `idx_friendly_match_shared_status` (`status`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+-- Optional rollback statements (manual use):
+-- DROP TABLE IF EXISTS `friendly_match_shared`;
+-- DROP TABLE IF EXISTS `friendly_match_invitation`;