Describe the bug
This is a follow up bug to: #713

While the previous bug and PR resolved issues with Parsing un-even indentation on comments, those indentations are not preserved. This is less than desirable if the goal is simply to edit a single field and preserve the rest of the files formatting.

The use-case here is modifying values.yaml files of helm charts that are human maintained. So we should not reformat the file and simply desire to use AST to select a field and update the value.

To Reproduce

Adding the following to TestComment cases will produce a failing test:

		{
			name: "commented values.yaml with uneven indentation",
			yaml: `
topLevelNode:
  attribute: true
  # comment about the next attribute
  # someOptInFeature: true
  allGoodSoFar: true
    # until this breaks it
  despair: true
`,
		},

Expected behavior
When yaml with un-even comments are parsed and modified, the un-even comments should maintain existing indent level (unless that was otherwise modified by the user.

So input of:

  allGoodSoFar: true
    # until this breaks it
  despair: true

Seeking to set despair to false should output:

  allGoodSoFar: true
    # until this breaks it
  despair: false

And not:

  allGoodSoFar: true
  # until this breaks it
  despair: false

Screenshots
N/A

Version Variables

• Go version: 1.24
• go-yaml's Version: 1.18.0

Additional context
Add any other context about the problem here.