FEATURE: Add runtime validation for index name field

[kalnode]

The index name field is type string however we also want to restrict it to: alphanumeric, dash, underscore and dot.

Barring using a validator library like Zod (should we?), it could be a simple function like so:

export function isValidName(str:string) {
    const regex = /^[a-zA-Z\-_.]+$/
    return regex.test(str)
}

Also look into: Unknown what Strapi validation features we could leverage, especially because we use our own custom types.

This validation should be applied to:

Admin pages:

• The HTML input field when creating an index
• Submission of the create index API

Server:

• Any function dealing with index name