Add JSON Type

[SpencerTorres]

Note: There are some server-side bugs that need to be fixed/merged, including a protocol update. However, this PR can still be reviewed as is.

Summary

Implement JSON column type. Fully resolves #1430.

Usage

The user can use JSON in 3 ways:

1. By using the new clickhouse.JSON type to assemble JSON data by path strings.
2. By using a struct or map. The struct can be any nested structure, but the map must be map[string]any.
3. By using strings. In this mode the user handles their own json.(Un)Marshal and the strings get sent to the server as-is.

The JSON column also supports the clickhouse.Dynamic type for handling a path with multiple data types. Structs can also include a tag to specify type, such as json:"my_field" chType:"Array(String)".

See examples folder for sample code.

Checklist

Delete items not relevant to your PR:

• Unit and integration tests covering the common scenarios were added

[SpencerTorres]

Updated with fixes and suggestions from Variant PR. There are still multiple server side bugs that will prevent certain features from working, but common scenarios work such as:

• Read/Write JSON using key/value pairs
• Write JSON using strings
• Read/Write JSON using structs (except stdlib sql)

Once #1454 is merged then we can see if any tests are broken in the test matrix. Tests are passing on latest Go/ClickHouse versions.

[SpencerTorres]

Looks like the tests are passing against main.

Note that JSON string tests are skipped while we wait for: ClickHouse/ClickHouse#73924

@jkaflik ready for review

[jkaflik]

LGTM. Lets have it merged and iterate in next steps.