fix(css_variables): wrong root dir if subdir has package.json #4127

Problem:
Root directory is incorrect for projects containing a `package.json` file in subdirectories.

For a project with a given file structure:

```
my-monorepo/
├── package.json
├── yarn.lock
├── css/
│   └── css-variables/
│       ├── color.css
│       └── typography.css
└── components/
    └── core/
        └── my-feature/
            ├── package.json           ← 2. causes LSP root to stop here
            ├── feature-component-a/
            │   └── feature-component-a.module.css           ← 1. current open buffer 
            └── feature-component-b/
                └── feature-component-b.module.css

```

The LSP is using `my-feature` as the root directory. This directory is not the one where the css variables are defined. It leads to an issue where the css variables are not indexed, and from `feature-component-a.module.css` auto-completion and jump to definition are not working.

Solution:
Using the same `root_dir` logic as `ts_ls` (which prefers lockfiles like yarn.lock or .git as root markers) correctly sets the project root to `my-monorepo/`, allowing `css/css-variables/` to be discoverable for the LSP.

0 files changed, 0 insertions, 0 deletions