implement an opinionated format command

[gotwarlost]

add a new fmt command that allows for formatting and checking the format of .hcl files. In the process convert any key value pairs inside object literals to always consistently use = instead of :.

It uses the std hclformat package for formatting.

A flag is present to turn off the key value normalizer. It may be removed once we have enough experience with the formatter in the wild.

[Copilot]

Pull Request Overview

This PR implements an opinionated format command for HCL files that standardizes object literal syntax from key: value to key = value while preserving the correct usage of colons in ternary expressions and for-expressions.

Key Changes

• Added a new fmt command with check mode and recursive directory processing capabilities
• Implemented token-based parsing to distinguish between object literal colons and expression colons
• Created comprehensive test coverage for various HCL syntax patterns including nested objects, ternaries, and for-expressions

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
internal/format/format.go	Core formatting logic with stack-based token processing to normalize object literal syntax
internal/format/format_test.go	Comprehensive test suite covering object literals, ternaries, for-expressions, and edge cases
internal/format/cmd.go	CLI implementation with file collection, stdin support, and check mode
cmd/fn-hcl-tools/tools.go	Command registration with flags for normalization, checking, and recursion
cmd/fn-hcl-tools/main.go	Integration of format command into main CLI

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[ydubreuil]

LGTM, very well done. I added a few nit comments for the tests.

[gotwarlost]

OK, I committed your suggestions but realized they were incorrect because the variables in the locals block are HCL attributes and cannot be assigned using : in the first place. I updated it to use a variant that assigns a local to an object that has a colon-delimited kv.