feat(buffer): render forge links as inline conceal overlays

Problem: forge tokens were stripped from the buffer and shown as EOL
virtual text via `%l`. The token disappeared from the editable line,
and multi-ref tasks broke.

Solution: compute `forge_spans` in `views.lua` with byte offsets for
each forge token in the rendered line. In `apply_inline_row()`, place
extmarks with `conceal=''` and `virt_text_pos='inline'` to visually
replace each raw token with its formatted label. Clear stale
`forge_spans` on dirty rows to prevent `end_col` out-of-range errors
after edits like `dd`.

lua/pending/buffer.lua

@@ -168,6 +168,19 @@ local function apply_inline_row(bufnr, row, m, icons)
       virt_text_pos = 'overlay',
       priority = 100,
     })
+    if m.forge_spans then
+      local forge = require('pending.forge')
+      for _, span in ipairs(m.forge_spans) do
+        local label_text, hl_group = forge.format_label(span.ref, span.cache)
+        vim.api.nvim_buf_set_extmark(bufnr, ns_inline, row, span.col_start, {
+          end_col = span.col_end,
+          conceal = '',
+          virt_text = { { label_text, hl_group } },
+          virt_text_pos = 'inline',
+          priority = 90,
+        })
+      end
+    end
   elseif m.type == 'header' then
     local line = vim.api.nvim_buf_get_lines(bufnr, row, row + 1, false)[1] or ''
     vim.api.nvim_buf_set_extmark(bufnr, ns_inline, row, 0, {
@@ -213,6 +226,7 @@ function M.reapply_dirty_inline(bufnr)
       local line = vim.api.nvim_buf_get_lines(bufnr, row - 1, row, false)[1] or ''
       local old_status = m.status
       m.status = infer_status(line) or m.status
+      m.forge_spans = nil
       log.debug(
         ('reapply_dirty: row=%d line=%q old_status=%s new_status=%s'):format(
           row,
@@ -379,10 +393,6 @@ local function setup_syntax(bufnr)
       syntax match taskCheckbox /\[!\]/ contained containedin=taskLine
       syntax match taskLine /^\/\d\+\/- \[.\] .*$/ contains=taskId,taskCheckbox
     ]])
-    local forge = require('pending.forge')
-    for _, pat in ipairs(forge.conceal_patterns()) do
-      vim.cmd('syntax match forgeRef /' .. pat .. '/ conceal contained containedin=taskLine')
-    end
   end)
 end
 

lua/pending/views.lua

@@ -1,6 +1,13 @@
 local config = require('pending.config')
+local forge = require('pending.forge')
 local parse = require('pending.parse')
 
+---@class pending.ForgeLineMeta
+---@field ref pending.ForgeRef
+---@field cache? pending.ForgeCache
+---@field col_start integer
+---@field col_end integer
+
 ---@class pending.LineMeta
 ---@field type 'task'|'header'|'blank'|'filter'
 ---@field id? integer
@@ -14,6 +21,7 @@ local parse = require('pending.parse')
 ---@field recur? string
 ---@field forge_ref? pending.ForgeRef
 ---@field forge_cache? pending.ForgeCache
+---@field forge_spans? pending.ForgeLineMeta[]
 
 ---@class pending.views
 local M = {}
@@ -43,6 +51,27 @@ local function format_due(due)
   return formatted
 end
 
+---@param task pending.Task
+---@param prefix_len integer
+---@return pending.ForgeLineMeta[]?
+local function compute_forge_spans(task, prefix_len)
+  local refs = forge.find_refs(task.description)
+  if #refs == 0 then
+    return nil
+  end
+  local cache = task._extra and task._extra._forge_cache or nil
+  local spans = {}
+  for _, r in ipairs(refs) do
+    table.insert(spans, {
+      ref = r.ref,
+      cache = cache,
+      col_start = prefix_len + r.start_byte,
+      col_end = prefix_len + r.end_byte,
+    })
+  end
+  return spans
+end
+
 ---@type table<string, integer>
 local status_rank = { wip = 0, pending = 1, blocked = 2, done = 3 }
 
@@ -178,6 +207,7 @@ function M.category_view(tasks)
       local prefix = '/' .. task.id .. '/'
       local state = state_char(task)
       local line = prefix .. '- [' .. state .. '] ' .. task.description
+      local prefix_len = #prefix + #('- [' .. state .. '] ')
       table.insert(lines, line)
       table.insert(meta, {
         type = 'task',
@@ -191,6 +221,7 @@ function M.category_view(tasks)
         recur = task.recur,
         forge_ref = task._extra and task._extra._forge_ref or nil,
         forge_cache = task._extra and task._extra._forge_cache or nil,
+        forge_spans = compute_forge_spans(task, prefix_len),
       })
     end
   end
@@ -231,6 +262,7 @@ function M.priority_view(tasks)
     local prefix = '/' .. task.id .. '/'
     local state = task.status == 'done' and 'x' or (task.priority > 0 and '!' or ' ')
     local line = prefix .. '- [' .. state .. '] ' .. task.description
+    local prefix_len = #prefix + #('- [' .. state .. '] ')
     table.insert(lines, line)
     table.insert(meta, {
       type = 'task',
@@ -245,6 +277,7 @@ function M.priority_view(tasks)
       recur = task.recur,
       forge_ref = task._extra and task._extra._forge_ref or nil,
       forge_cache = task._extra and task._extra._forge_cache or nil,
+      forge_spans = compute_forge_spans(task, prefix_len),
     })
   end