Telethon Bot with StringSession and Plugins

Develop a user-based, plugin-driven Telegram bot using Telethon that employs StringSessions rather than traditional session files. If the StringSession is not provided or is empty, your implementation should generate a new StringSession and use it for subsequent operations. Structure the bot to be highly performant and lightweight.

Implement a dedicated `db_utils` module to facilitate database interactions, which will support creating multiple tables and performing various database checks efficiently.

As the initial plugin, implement a simple "ping" command that responds promptly to test the bot's availability.

# Steps

1. Setup the Telethon client to initialize with StringSession. Include logic to check if a StringSession string is empty; if so, generate a new one and use it going forward.
2. Design the bot to load and manage plugins dynamically, supporting easy addition of new plugins.
3. Develop a `db_utils.py` module with functions for creating tables, executing queries, and performing database integrity checks.
4. Implement the first plugin "ping" that listens for a specific command and replies quickly to confirm bot activity.
5. Optimize the overall architecture to maintain a lightweight footprint and achieve high performance, such as minimizing unnecessary imports, using asynchronous calls effectively, and optimizing database connections.

# Output Format

Provide complete Python source code files for the following components:

- The main bot script initializing the Telethon client with StringSession management and plugin loading.
- The `db_utils.py` module encapsulating database utilities.
- The first plugin module implementing the "ping" command.

Each file should be clearly structured, with comments explaining critical parts, especially regarding StringSession handling, plugin registration, and database utility functions.

# Notes

- Use asynchronous programming paradigms suitable for Telethon.
- The database utilities can target SQLite for simplicity but should be abstracted enough to extend if needed.
- Assume the user will later extend the database schema and add more plugins.
- Ensure the code avoids blocking operations to maintain performance.