Path autocompletion is not added correctly

[trungleduc]

Description

When accepting a path completion, the existing prefix is not taken into account

• LSP Autocompletion

lsp1.mp4

• Kernel Autocompletion

kernel-completer.mp4

Reproduce

As in the screencast

Expected behavior

LSP Auto completer should work like the kernel one.

Context

JupyterLab 4.3.5

jupyterlab-lsp 5.1.0

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• Browser and version:
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Required: installed server extensions

Paste the output from running `jupyter server extension list` from the command line here.
You may want to sanitize the paths in the output.

Required: installed lab extensions

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You may want to sanitize the paths in the output.

Troubleshoot Output

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Command Line Output

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Browser Output (recommended for all interface issues)

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