feat(views): add recurrence to LineMeta

Problem: LineMeta does not carry recurrence info, so the buffer
layer cannot display recurrence indicators.

Solution: add recur field to LineMeta and populate it in both
category_view() and priority_view().

lua/pending/views.lua

@@ -10,6 +10,7 @@ local config = require('pending.config')
 ---@field overdue? boolean
 ---@field show_category? boolean
 ---@field priority? integer
+---@field recur? string
 
 ---@class pending.views
 local M = {}
@@ -149,6 +150,7 @@ function M.category_view(tasks)
         status = task.status,
         category = cat,
         overdue = task.status == 'pending' and task.due ~= nil and task.due < today or nil,
+        recur = task.recur,
       })
     end
   end
@@ -200,6 +202,7 @@ function M.priority_view(tasks)
       category = task.category,
       overdue = task.status == 'pending' and task.due ~= nil and task.due < today or nil,
       show_category = true,
+      recur = task.recur,
     })
   end