add a storage plugin

[hjlarry]

It can store or retrieve strings and files, as well as share the file's URL via the endpoint.

[LogicOber]

Hello @hjlarry 👋 We really appreciate your plugin’s value and the effort you’ve put into it, and we’d like to suggest a few improvements for a better overall experience.

• First, we recommend using a more visually appealing icon that reflects your unique brand identity, though that is only a friendly suggestion rather than a requirement. 🙂
• But it's essential to enhance the YAML file parameters by offering clearer and more detailed human descriptions instead of repeating the parameter names; this will help users fully understand each field’s purpose.
• We also notice that the current set_file, delete, and get logic lacks permission checks, which could let anyone with the key access or remove content; could you confirm if this is intentional? We suggest building a more robust authorization flow to protect users.
• Additionally, please add a PRIVACY.md file to clarify how user data is collected, stored, and handled, and consider expanding your README.md by showing concise examples for each tool’s inputs, outputs and examples of endpoint so new users can quickly understand how your plugin works.

Looking forward to your updates and hope your plugin becomes popular! 🔥