[BUG] Crash when including certain contexts

[DemvSteinbrink]

In certain cases (I haven't exactly pinned down which ones), adding context via @foo causes the following error:

Error executing vim.schedule lua callback: ...hare/nvim/plugged/tabnine-nvim/lua/tabnine/chat/init.lua:357: Invalid 'end_col': Expected Lua number                                                                  
stack traceback:                                                                                                                                                                                                    
        [C]: in function 'nvim_buf_get_text'                                                                                                                                                                        
        ...hare/nvim/plugged/tabnine-nvim/lua/tabnine/chat/init.lua:357: in function 'func'                                                                                                                         
        vim/shared.lua:257: in function 'tbl_map'                                                                                                                                                                   
        ...hare/nvim/plugged/tabnine-nvim/lua/tabnine/chat/init.lua:354: in function 'handler'                                                                                                                      
        ...re/nvim/plugged/tabnine-nvim/lua/tabnine/chat/binary.lua:85: in function 'fn'                                                                                                                            
        vim/_editor.lua:351: in function <vim/_editor.lua:350>

To Reproduce
Open TabnineChat, ask a prompt with some @foo context, in some cases the above error pops up.

Expected behavior
No errors

Version Info:

• OS: GNU/Linux trixie/sid
• Neovim version: NVIM v0.10.4
• Installed Tabnine Binaries 4.245.0
• Active Tabnine Binaries: There is no .active file