Update lsp to new api

This updates from the old lspconfig plugins to the new lua lsp api and
removes my old ccls config.

nvim/lua/nvim-cmp.lua

@@ -45,38 +45,11 @@ cmp.setup.cmdline(':', {
   matching = { disallow_symbol_nonprefix_matching = false }
 })
 
-
--- Set up lspconfig.
-local capabilities = require('cmp_nvim_lsp').default_capabilities()
-local lsp = require('lspconfig')
-
--- lsp.ccls.setup{
---     capabilities = capabilities,
---     init_options = {
---         cache = {
---             directory = vim.fn.expand("~/.cache/ccls")  -- Store index globally
---         },
---         compilationDatabaseDirectory = "build",  -- Uses 'build/compile_commands.json' if present
---         highlight = { lsRanges = true },  -- Improves semantic highlighting
---         index = {
---             threads = 4,  -- Adjust based on your CPU (more threads = faster indexing)
---             initialBlacklist = { ".*_test.cpp", ".*_unittest.cpp" }
---             -- initialBlacklist = { ".*_test.cpp", ".*_unittest.cpp", "/home/furtest/linux_bidouille/.*" }  -- Avoid indexing test files
---         },
---         completion = {
---             detailedLabel = true  -- Better completion info
---         },
---         diagnostics = {
---             onChange = 300  -- Delay diagnostics updates for better performance
---         }
---     }
--- }
-
-
--- clangd and ccls are both C and C++ language servers
--- having them both active at the same time is useless
-lsp.clangd.setup {
-    capabilities = capabilities,
-    cmd = { "clangd", "--enable-config" },
+vim.lsp.config.clangd = {
+  cmd = { 'clangd', '--background-index' },
+  root_markers = { 'compile_commands.json', 'compile_flags.txt', '.clangd' },
+  filetypes = { 'c', 'cpp' },
 }
 
+vim.lsp.enable({'clangd'})
+