Support pygls 2

[polyzen]

Test failure:

======================================================================        
ERROR: test_lsp (ufmt.tests.cli.CliTest.test_lsp)                             
----------------------------------------------------------------------        
Traceback (most recent call last):                                            
  File "/usr/lib/python3.13/unittest/mock.py", line 1423, in patched          
    with self.decoration_helper(patched,                                      
         ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^                                      
                                args,                                         
                                ^^^^^                                         
                                keywargs) as (newargs, newkeywargs):          
                                ^^^^^^^^^                                     
  File "/usr/lib/python3.13/contextlib.py", line 141, in __enter__            
    return next(self.gen)                                                     
  File "/usr/lib/python3.13/unittest/mock.py", line 1405, in decoration_helper
    arg = exit_stack.enter_context(patching)                                  
  File "/usr/lib/python3.13/contextlib.py", line 530, in enter_context        
    result = _enter(cm)                                                       
  File "/usr/lib/python3.13/unittest/mock.py", line 1481, in __enter__        
    self.target = self.getter()                                               
                  ~~~~~~~~~~~^^                                               
  File "/usr/lib/python3.13/pkgutil.py", line 528, in resolve_name            
    result = getattr(result, p)                                               
AttributeError: module 'ufmt' has no attribute 'lsp'                          
                                                                              
----------------------------------------------------------------------        

Output from ufmt lsp:

Traceback (most recent call last):
  File "/usr/bin/ufmt", line 8, in <module>
    sys.exit(main())
             ~~~~^^
  File "/usr/lib/python3.13/site-packages/click/core.py", line 1442, in __call__
    return self.main(*args, **kwargs)
           ~~~~~~~~~^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.13/site-packages/click/core.py", line 1363, in main
    rv = self.invoke(ctx)
  File "/usr/lib/python3.13/site-packages/click/core.py", line 1830, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^
  File "/usr/lib/python3.13/site-packages/click/core.py", line 1226, in invoke
    return ctx.invoke(self.callback, **ctx.params)
           ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.13/site-packages/click/core.py", line 794, in invoke
    return callback(*args, **kwargs)
  File "/usr/lib/python3.13/site-packages/click/decorators.py", line 34, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/usr/lib/python3.13/site-packages/ufmt/cli.py", line 188, in lsp
    from .lsp import ufmt_lsp
  File "/usr/lib/python3.13/site-packages/ufmt/lsp.py", line 17, in <module>
    from pygls.server import LanguageServer
ImportError: cannot import name 'LanguageServer' from 'pygls.server' (/usr/lib/python3.13/site-packages/pygls/server.py)