Replace old team system with work teams (equipos de trabajo)

- New migration 003_teams.sql: teams, team_user, team_server tables
- New Team model with CRUD, members, and server assignment
- New TeamController with full team management
- New views: teams/index, teams/create, teams/show
- Server model: getUserRole and getAccessibleServerIds now include team-based access
- Sidebar: Teams link under Administration (admin+ only)
- Routes: old /team routes removed, new /teams routes added
- Removed old ServerController team methods and views
- Fixed sidebar empty accessible IDs returning all servers
- Fixed dashboard and API to show empty when no accessible servers

database/migrations/003_teams.sql

@@ -0,0 +1,47 @@
+-- ============================================================================
+-- ServerManager Teams
+-- Team-based access control: teams group users and servers together
+-- ============================================================================
+
+CREATE TABLE IF NOT EXISTS `teams` (
+    `id` INT UNSIGNED NOT NULL AUTO_INCREMENT,
+    `name` VARCHAR(100) NOT NULL,
+    `description` TEXT DEFAULT NULL,
+    `created_by` INT UNSIGNED NOT NULL,
+    `created_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    `updated_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+    PRIMARY KEY (`id`),
+    KEY `idx_name` (`name`),
+    KEY `idx_created_by` (`created_by`),
+    CONSTRAINT `fk_teams_created_by` FOREIGN KEY (`created_by`)
+        REFERENCES `users` (`id`) ON DELETE CASCADE ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+CREATE TABLE IF NOT EXISTS `team_user` (
+    `id` INT UNSIGNED NOT NULL AUTO_INCREMENT,
+    `team_id` INT UNSIGNED NOT NULL,
+    `user_id` INT UNSIGNED NOT NULL,
+    `created_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    PRIMARY KEY (`id`),
+    UNIQUE KEY `uk_team_user` (`team_id`, `user_id`),
+    KEY `idx_user_id` (`user_id`),
+    CONSTRAINT `fk_team_user_team` FOREIGN KEY (`team_id`)
+        REFERENCES `teams` (`id`) ON DELETE CASCADE ON UPDATE CASCADE,
+    CONSTRAINT `fk_team_user_user` FOREIGN KEY (`user_id`)
+        REFERENCES `users` (`id`) ON DELETE CASCADE ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+CREATE TABLE IF NOT EXISTS `team_server` (
+    `id` INT UNSIGNED NOT NULL AUTO_INCREMENT,
+    `team_id` INT UNSIGNED NOT NULL,
+    `server_id` INT UNSIGNED NOT NULL,
+    `role` ENUM('viewer', 'manager') NOT NULL DEFAULT 'viewer',
+    `created_at` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    PRIMARY KEY (`id`),
+    UNIQUE KEY `uk_team_server` (`team_id`, `server_id`),
+    KEY `idx_server_id` (`server_id`),
+    CONSTRAINT `fk_team_server_team` FOREIGN KEY (`team_id`)
+        REFERENCES `teams` (`id`) ON DELETE CASCADE ON UPDATE CASCADE,
+    CONSTRAINT `fk_team_server_server` FOREIGN KEY (`server_id`)
+        REFERENCES `servers` (`id`) ON DELETE CASCADE ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;