Add indentation parameter to json_format function

[aayushsh06]

Description

Adds additional formatting options for JSON by overloading the existing json_format function with a indentSpaces parameter to add formatting without impacting precision.

Additional context and related issues

json_format currently outputs compact JSON, which is hard to read in tools that display raw strings. Adding optional pretty-printing improves readability without losing precision, especially for clients like Grafana that mishandle large integers when parsing JSON. This feature is fully backward-compatible and opt-in.
Related to #27113

Release notes

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[cla-bot]

Thank you for your pull request and welcome to the Trino community. We require contributors to sign our Contributor License Agreement, and we don't seem to have you on file. Continue to work with us on the review and improvements in this PR, and submit the signed CLA to [email protected]. Photos, scans, or digitally-signed PDF files are all suitable. Processing may take a few days. The CLA needs to be on file before we merge your changes. For more information, see https://github.com/trinodb/cla

[cla-bot]

Thank you for your pull request and welcome to the Trino community. We require contributors to sign our Contributor License Agreement, and we don't seem to have you on file. Continue to work with us on the review and improvements in this PR, and submit the signed CLA to [email protected]. Photos, scans, or digitally-signed PDF files are all suitable. Processing may take a few days. The CLA needs to be on file before we merge your changes. For more information, see https://github.com/trinodb/cla