refactor(misconf): migrate from custom Azure JSON parser

[nikpivkin]

Description

This PR replaces the custom JSON parser with github.com/go-json-experiment/json for parsing ARM templates. This significantly simplifies the codebase and reduces maintenance overhead.

Instead of manually parsing the JSON structure, and positional information, the unmarshaler from github.com/go-json-experiment/json and some helper functions from x/json are now used.

The only non-trivial part of the migration was correctly initializing the metadata object with:
• file system (fs.FS),
• file path,
• range (position of the node in the source file),
• reference to the corresponding JSON node in the tree.

To support populating this metadata during decoding, a hook system was introduced. Currently, only the After hook is implemented. It is triggered after decoding each object and provides access to:
• decoder,
• decoded object,
• source location of the JSON node.

Related issues

• Close refactor(azure): migrate from custom JSON parser #9025

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Checklist

• I've read the guidelines for contributing to this repository.
• I've followed the conventions in the PR title.
• I've added tests that prove my fix is effective or that my feature works.
• I've updated the documentation with the relevant information (if needed).
• I've added usage information (if the PR introduces new options)
• I've included a "before" and "after" example to the description (if the PR is a user interface change).

[Copilot]

Pull Request Overview

This PR refactors the Azure ARM parser to replace a custom JSON parser with the standardized github.com/go-json-experiment/json library. This modernization simplifies the codebase significantly by removing approximately 1,500 lines of custom parsing logic while maintaining equivalent functionality.

• Replaced custom armjson parsing library with go-json-experiment/json
• Introduced a hook system for capturing metadata during JSON unmarshaling
• Updated Value struct to use pointer-based metadata management

Reviewed Changes

Copilot reviewed 42 out of 42 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
pkg/x/json/json.go	Enhanced with generic hooks and location tracking capabilities
pkg/iac/scanners/azure/value.go	Refactored to implement json.UnmarshalerFrom interface
pkg/iac/scanners/azure/arm/parser/template.go	New ParseTemplate function with metadata collection system
pkg/iac/scanners/azure/arm/parser/parser.go	Simplified to use new ParseTemplate function
Multiple armjson files	Removed entire custom JSON parser implementation

Comments suppressed due to low confidence (1)

pkg/iac/scanners/azure/arm/parser/template.go:69

• Field name 'Loc' is inconsistent with other fields and unclear. It should be renamed to 'Location' to match the original field name and improve readability.

	Loc        azure.Value `json:"location"`

[simar7]

@nikpivkin although somewhat unrelated - I recall us not being able to save positional arguments for helm charts. Could we use a similar hook based approach for that too?

[nikpivkin]

@nikpivkin although somewhat unrelated - I recall us not being able to save positional arguments for helm charts. Could we use a similar hook based approach for that too?

Are you referring to the positions in the original Helm templates? I don't think that's possible. I left a comment in this discussion.

[simar7]

Any reason to change the field? Location seems self explanatory.

[simar7]

lgtm, just left one small nit.