refactor: Fix PSR-12 and documentation issues

- Consolidate duplicate documentation sections
- Move Internationalization section after Plugin Views
- Remove redundant Example Plugin Structure and View Hooks sections
- Fix PSR-12 brace style in plugin_helper.php
- Fix PSR-12 brace style in PluginInterface.php (remove unnecessary PHPdocs)
- Fix PSR-12 brace style in BasePlugin.php (remove unnecessary PHPdocs)
- Use log_message() instead of error_log() in migration
- Add IF NOT EXISTS to plugin_config table creation for resilience
- Convert snake_case to camelCase for class names throughout docs

app/Database/Migrations/sqlscripts/3.4.1_PluginConfigTableCreate.sql

@@ -1,8 +1,7 @@
-CREATE TABLE `ospos_plugin_config` (
+CREATE TABLE IF NOT EXISTS `ospos_plugin_config` (
     `key` varchar(100) NOT NULL,
     `value` text NOT NULL,
     `created_at` timestamp NOT NULL DEFAULT current_timestamp(),
-    `updated_at` timestamp NOT NULL DEFAULT current_timestamp() ON UPDATE current_timestamp()
-) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
-
-ALTER TABLE `ospos_plugin_config` ADD PRIMARY KEY (`key`);
+    `updated_at` timestamp NOT NULL DEFAULT current_timestamp() ON UPDATE current_timestamp(),
+    PRIMARY KEY (`key`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;