Progress.tokens accumulates entries forever

[meymchen]

Component

pygls/progress.py

Summary

Progress.begin and Progress.create register tokens in a dictionary, but Progress.end never removes them. A long-running server that reports frequent progress will leak Future objects and token entries without bound.

Steps to Reproduce

1. Report work-done progress repeatedly over hours.
2. Observe that len(lsp.protocol.progress.tokens) grows monotonically.

Expected Behavior

Tokens should be cleaned up when progress ends.

Actual Behavior

Tokens remain in memory forever.

Affected Code (pygls/progress.py, ~L77-79)

def end(self, token, value):
    self._lsp.notify(PROGRESS, ProgressParams(token=token, value=value))

Proposed Fix

def end(self, token, value):
    self.tokens.pop(token, None)
    self._lsp.notify(PROGRESS, ProgressParams(token=token, value=value))