- Introduce a field in NDC `Configuration` struct that carries an
optional limit (`usize`) value.
- When set, reject NDC response that is greater than the limit.
- Define a `HttpContext` struct that captures both `reqwest::Client` and
an optional limit value. Replace the `http_client` argument with
`http_context: &HttpContext` in all execute related functions.
- The `execute_query` function caller in multitenant code need to pass a
reference to `HttpContext` with appropriate NDC response size limit.
V3_GIT_ORIGIN_REV_ID: 85a3647c4d136cc8d887f343736cc011166f036f
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## Description
This moves all the crates into a `/crates` folder. Everything appears to
just work, thanks Cargo!
V3_GIT_ORIGIN_REV_ID: 8e3ef287b1a46cabdb4d919a50e813ab2cddf8b1
