Describe the bug
When inserting function parameters, the signature hint window appears after the initial open paren, then disappears while typing. Additionally, invoking signature.show while in insert mode often does not trigger the signature window. This seems to be related to other content in the parens and whether the closing paren is present.

Expected behavior
The signature hint window should show in insert mode according to the default config, and also when triggered.

Steps to reproduce

• Open a .scd file and start scnvim
• Insert a function and an open paren, eg, LPF.ar(| (where | is the cursor)
• Signature hint window appears
• While still in insert mode, insert any characters
• Signature hint window disappears
• Close the paren, eg, LPF.ar(something)|
• Return to normal mode with <ESC> then enter insert mode with ci(, resulting in LPF.ar(|)
• While still in insert mode, trigger signature.show (with a keybind, <C-k> using the below vimrc)
• Signature hint window does not appear

Additional context
This can be reproduced using this minimal config (eg, with nvim -u testconfig.vimrc, using vim-plug):

call plug#begin()
Plug 'davidgranstrom/scnvim'
call plug#end()

lua << EOF
local scnvim = require('scnvim')
scnvim.setup({
    keymaps = {
        ['<C-k>'] = scnvim.map('signature.show', {'n', 'i'}),
    }
})
EOF

Sorry for the long explanation, this one got slipperier the more I investigated. It has always been this way on my system, so it's not a new thing, I only just got around to trying to fix it...

Information

• Operating system
  Pop!_OS 22.04

• SuperCollider version
  3.11.12

• nvim --version

NVIM v0.10.0-dev                                                                                                                          
Build type: RelWithDebInfo                                                                                                                
LuaJIT 2.1.0-beta3

• Package manager
  vim-plug