More markdownlint rules triggered from CLI than from efm

Invoking markdownlint from the CLI triggers more rules than invoking it via efm-langserver in Neovim.

Example Markdown:

# This line triggers MD043

This line should trigger MD013. This line should trigger MD013. This line should trigger MD013.

Both rules triggered on CLI:

$ markdownlint -c "$HOME/.markdownlint.yaml" TEST.md
TEST.md:1 MD043/required-headings Required heading structure [Expected: [None]; Actual: # This line triggers MD043]
TEST.md:3:81 MD013/line-length Line length [Expected: 80; Actual: 95]

efm-langserver in Neovim only shows MD043. I confirmed that both are using $HOME/.markdownlint.yaml. That is, if I disable all rules, efm-langserver stops showing MD043.

markdownlint: &markdownlint
  lint-command: 'markdownlint -s -c "$HOME/.markdownlint.yaml"'
  lint-stdin: true
  lint-formats:
    - '%f:%l %m'
    - '%f:%l:%c %m'
    - '%f: %l: %m'

I have never had this issue with any other command.

NVIM v0.10.0
efm-langserver 0.0.53
markdownlint 0.41.0

Reproduce the discrepancy using the shown markdownlint command and the efm-langserver configuration in Neovim, with the provided Markdown and markdownlint configuration. Compare how CLI output from stdin is handled and how diagnostics are parsed; done means MD043 and MD013 are both surfaced through efm as they are from the CLI.