feat: Add follow_cursor and restore_location

New lua API function: follow_cursor (supports opts.focus_outline).
This sets location in outline to match location in code.

New keymap: restore_location (C-g) by default.
This provides the same functionality as follow_cursor.

I've also refactored other lua API functions for consistency of using
`opts.focus_outline`. If opts is not provided, focus_outline is
defaulted to true. To change this behaviour, set it to false.

lua/symbols-outline/providers/coc.lua

@@ -83,11 +83,12 @@ local function convert_symbols(result)
 end
 
 ---@param on_symbols function
-function M.request_symbols(on_symbols)
+---@param opts table
+function M.request_symbols(on_symbols, opts)
   vim.fn.call('CocActionAsync', {
     'documentSymbols',
     function(_, symbols)
-      on_symbols { [1000000] = { result = convert_symbols(symbols) } }
+      on_symbols({ [1000000] = { result = convert_symbols(symbols) } }, opts)
     end,
   })
 end

lua/symbols-outline/providers/init.lua

@@ -21,13 +21,13 @@ function M.has_provider()
 end
 
 ---@param on_symbols function
-function M.request_symbols(on_symbols)
+function M.request_symbols(on_symbols, opts)
   for _, value in ipairs(providers) do
     local provider = require(value)
     if provider.should_use_provider(0) then
       _G._symbols_outline_current_provider = provider
       _G._symbols_outline_current_provider.name = value
-      provider.request_symbols(on_symbols)
+      provider.request_symbols(on_symbols, opts)
       break
     end
   end

lua/symbols-outline/providers/markdown.lua

@@ -17,8 +17,9 @@ function M.hover_info(_, _, on_info)
 end
 
 ---@param on_symbols function
-function M.request_symbols(on_symbols)
-  on_symbols(md_parser.handle_markdown())
+---@param opts table
+function M.request_symbols(on_symbols, opts)
+  on_symbols(md_parser.handle_markdown(), opts)
 end
 
 return M

lua/symbols-outline/providers/nvim-lsp.lua

@@ -69,13 +69,14 @@ function M.postprocess_symbols(response)
 end
 
 ---@param on_symbols function
-function M.request_symbols(on_symbols)
+function M.request_symbols(on_symbols, opts)
   vim.lsp.buf_request_all(
     0,
     'textDocument/documentSymbol',
     getParams(),
     function (response)
-      on_symbols(M.postprocess_symbols(response))
+      response = M.postprocess_symbols(response)
+      on_symbols(response, opts)
     end
   )
 end