fix: =$= and =0= motions for calendar view (#987)

* fix: config =$= and =0= motions for calendar view

* fix: line string beginning index

Co-authored-by: Kristijan Husak <husakkristijan@gmail.com>

* fix: line string ending index

Co-authored-by: Kristijan Husak <husakkristijan@gmail.com>

---------

Co-authored-by: Kristijan Husak <husakkristijan@gmail.com>

Author: celsobenedetti

lua/orgmode/objects/calendar.lua

@@ -130,6 +130,12 @@ function Calendar:open()
   vim.keymap.set('n', '<Left>', function()
     return self:cursor_left()
   end, map_opts)
+  vim.keymap.set('n', '0', function()
+    return self:beginning()
+  end, map_opts)
+  vim.keymap.set('n', '$', function()
+    return self:ending()
+  end, map_opts)
   vim.keymap.set('n', '<Right>', function()
     return self:cursor_right()
   end, map_opts)
@@ -436,6 +442,27 @@ function Calendar:cursor_left()
   self:render()
 end
 
+function Calendar:beginning()
+  if self.select_state ~= SelState.DAY then
+    return
+  end
+  local line = vim.fn.line('.')
+  vim.fn.cursor(line, vim.fn.getline('.'):match('^%s*'):len() + 1)
+  self.date = self:get_selected_date()
+  self:render()
+end
+
+function Calendar:ending()
+  if self.select_state ~= SelState.DAY then
+    return
+  end
+  local line = vim.fn.line('.')
+  local line_no_trailing_space = vim.fn.getline('.'):gsub('%s*$', '')
+  vim.fn.cursor(line, line_no_trailing_space:len())
+  self.date = self:get_selected_date()
+  self:render()
+end
+
 ---@param direction string
 ---@param step_size number
 ---@param current number