Keybindings and smaller ui related improvements

Options:

- lualine shows path of files
- added breadcrumbs to programming buffers as winbar

Plugins:

- added mrcjkb/rustaceanvim for improved rust support
- added lewis6991/gitsigns.nvim to show changes in files
- dropped lspkind, it had no visible effect and could not easily be
  fixed
- added j-hui/fidget.nvim to make $/progress messages (e.g. from lsp)
  visible

Keybindings:

- dropped unused and commented out keybindings
- <leader>fr to resume last fzf search
- <C-W>0, 1, 2, 3 to mimic emacs <C-x>.... window keys
- <esc><esc> to clear last search
- added desc field to many keybindings in lsp

lua/lsp.lua

@@ -13,7 +13,7 @@ require('mason-lspconfig').setup({
   ensure_installed = {
     'pylsp',
     'lua_ls',
-    'rust_analyzer',
+    -- 'rust_analyzer', -- handled by rust mrcjkb/rustaceanvim
     'yamlls',
     'ts_ls',
     'gopls',
@@ -22,45 +22,33 @@ require('mason-lspconfig').setup({
   },
 })
 
--- Customized on_attach function
--- See `:help vim.diagnostic.*` for documentation on any of the below functions
-local opts = { noremap = true, silent = true }
-vim.keymap.set('n', '<space>e', vim.diagnostic.open_float, { noremap = true, silent = true, desc = "Popup diagnostics" })
--- 2024-09-23 - currently unused
--- vim.keymap.set('n', '<space>q', vim.diagnostic.setloclist, opts)
-vim.keymap.set('n', '[d', vim.diagnostic.goto_prev, opts)
-vim.keymap.set('n', ']d', vim.diagnostic.goto_next, opts)
 
 -- Use an on_attach function to only map the following keys
 -- after the language server attaches to the current buffer
 local on_attach = function(client, bufnr)
   -- Enable completion triggered by <c-x><c-o>
-  vim.api.nvim_buf_set_option(bufnr, 'omnifunc', 'v:lua.vim.lsp.omnifunc')
+  -- vim.api.nvim_buf_set_option(bufnr, 'omnifunc', 'v:lua.vim.lsp.omnifunc')
 
   -- See `:help vim.lsp.*` for documentation on any of the below functions
   local bufopts = { noremap = true, silent = true, buffer = bufnr }
-  vim.keymap.set('n', 'gD', vim.lsp.buf.declaration, bufopts)
-  vim.keymap.set('n', 'gd', vim.lsp.buf.definition, bufopts)
-  vim.keymap.set('n', 'K', vim.lsp.buf.hover, bufopts)
-  vim.keymap.set('n', 'gi', vim.lsp.buf.implementation, bufopts)
-  vim.keymap.set('n', '<C-k>', vim.lsp.buf.signature_help, bufopts)
-  vim.keymap.set('n', '<space>wa', vim.lsp.buf.add_workspace_folder, bufopts)
-  vim.keymap.set('n', '<space>wr', vim.lsp.buf.remove_workspace_folder, bufopts)
+  vim.keymap.set('n', 'K', vim.lsp.buf.hover, { desc = "LSP show signature", unpack(bufopts) })
+  vim.keymap.set('n', '<space>wa', vim.lsp.buf.add_workspace_folder,
+    { desc = "Workspace add folder", unpack(bufopts) })
+  vim.keymap.set('n', '<space>wr', vim.lsp.buf.remove_workspace_folder,
+    { desc = "Workspace remove folder", unpack(bufopts) })
   vim.keymap.set('n', '<space>wl', function()
     print(vim.inspect(vim.lsp.buf.list_workspace_folders()))
-  end, bufopts)
-  -- vim.keymap.set('n', '<space>D', vim.lsp.buf.type_definition, bufopts)
-  vim.keymap.set('n', '<space>rn', vim.lsp.buf.rename, bufopts)
-  -- vim.keymap.set('n', '<space>ca', vim.lsp.buf.code_action, bufopts)
+  end, { desc = "Workspace list folders", unpack(bufopts) })
+  vim.keymap.set('n', '<space>rn', vim.lsp.buf.rename, { desc = "LSP Rename", unpack(bufopts) })
   vim.keymap.set("n", "<space>f", function()
     vim.lsp.buf.format({ async = true })
-  end, bufopts)
+  end, { desc = "LSP Format buffer", unpack(bufopts) })
 
   -- 2024-09-09 - some ccflow commands
-
   local fzf = require('fzf-lua')
   vim.keymap.set('n', '<space>d', fzf.diagnostics_document, { desc = "Document diagnostics" })
   vim.keymap.set('n', '<space>D', fzf.diagnostics_workspace, { desc = "Workspace diagnostics" })
+  vim.keymap.set('n', '<space>e', vim.diagnostic.open_float, { desc = "Popup diagnostics" })
   vim.keymap.set('n', '<space>s', fzf.lsp_document_symbols, { desc = "Doc symbols" })
   vim.keymap.set('n', '<space>c', fzf.lsp_code_actions, { desc = "Code Actions" })
   -- vim.keymap.set('n', 'gr', vim.lsp.buf.references, bufopts)
@@ -69,7 +57,7 @@ local on_attach = function(client, bufnr)
 end
 
 -- Set different settings for different languages' LSP
--- LSP list: https://github.com/neovim/nvim-lspconfig/blob/master/doc/server_configurations.md
+-- LSP list: https://github.com/neovim/nvim-lspconfig/blob/master/doc/configs.md
 -- How to use setup({}): https://github.com/neovim/nvim-lspconfig/wiki/Understanding-setup-%7B%7D
 --     - the settings table is sent to the LSP
 --     - on_attach: a lua callback function to run after LSP attaches to a given buffer
@@ -108,3 +96,12 @@ require('mason-lspconfig').setup_handlers({
     end
   end
 })
+
+
+-- use on_attach to get lsp related shortcuts
+vim.g.rustaceanvim = {
+  -- LSP configuration
+  server = {
+    on_attach = on_attach
+  }
+}