feat(avatar): implement avatar upload processing and validation, update user interface for avatar display

config/database.php

@@ -146,6 +146,7 @@ function ensure_tables_exist(PDO $pdo): void {
             "ALTER TABLE users ADD COLUMN notification_settings TEXT NULL AFTER remember_token_expires_at",
             "ALTER TABLE users ADD COLUMN theme VARCHAR(20) NOT NULL DEFAULT 'dark' AFTER notification_settings",
             "ALTER TABLE users ADD COLUMN avatar_url VARCHAR(255) NULL AFTER theme",
+            "ALTER TABLE users MODIFY COLUMN avatar_url MEDIUMTEXT NULL",
             "ALTER TABLE users ADD COLUMN backup_codes TEXT NULL AFTER two_factor_enabled",
             "ALTER TABLE users ADD COLUMN default_jira_filter_code VARCHAR(50) NULL AFTER avatar_url",
             "ALTER TABLE users ADD COLUMN fociz_widget_layout TEXT NULL AFTER default_jira_filter_code",

config/schema.sql

@@ -13,7 +13,7 @@ CREATE TABLE IF NOT EXISTS `users` (
   `remember_token` VARCHAR(64) NULL,
   `remember_token_expires_at` DATETIME NULL,
   `notification_settings` TEXT NULL,
-  `avatar_url` VARCHAR(255) NULL,
+  `avatar_url` MEDIUMTEXT NULL,
   `default_jira_filter_code` VARCHAR(50) NULL,
   `fociz_widget_layout` TEXT NULL,
   `last_mail_check_at` DATETIME NULL,