Consider adding __cdk_name #317

I've opened this issue with 3 additional CDK projects:

• Motoko
• Azle
• Kybra

As we've been developing CDKs (TypeScript/JavaScript with Azle and Python with Kybra), we've been thinking about how to measure adoption of various CDKs. In addition to GitHub metrics (such as analyzing dfx.json), it might be a powerful metric to know exactly how many canisters use a particular CDK. For Azle and Kybra, we're adding a simple method __cdk_name that returns a string with the name of the CDK. This will allow canister indexers like https://icscan.io/ to index canisters by CDK. This could allow viewing of various CDK metrics over time, which I think would be very interesting to many different parties on the IC.

Here's our suggested implementation of the method in cdk-rs:

#[ic_cdk_macros::query]
fn __cdk_name() -> String {
    "cdk-rs".to_string()
}

Here's our suggested implementation of the method in Azle:

#[ic_cdk_macros::query]
fn __cdk_name() -> String {
    "azle".to_string()
}

Here's our suggested implementation of the method in Kybra:

#[ic_cdk_macros::query]
fn __cdk_name() -> String {
    "kybra".to_string()
}

Do you have any thoughts on this pattern?