feat: text objects and motions for the pending buffer (#39)

* feat: text objects and motions for the pending buffer

Problem: the pending buffer has action-button mappings but no Vim
grammar. You cannot dat to delete a task, cit to change a description,
or ]] to jump to the next category header.

Solution: add textobj.lua with at/it (a task / inner task), aC/iC
(a category / inner category), ]]/[[ (next/prev header), and ]t/[t
(next/prev task). All text objects work in operator-pending and visual
modes; motions work in normal, visual, and operator-pending. Mappings
are configurable via the keymaps table and exposed as <Plug> mappings.

* fix(textobj): escape Lua pattern hyphen, fix test expectations

Problem: inner_task_range used unescaped '-' in Lua patterns, which
acts as a lazy quantifier instead of matching a literal hyphen. The
metadata-stripping logic also tokenized the full line including the
prefix, so the rebuilt string could never be found after the prefix.
All test column expectations were off by one.

Solution: escape hyphens with %-, rewrite metadata stripping to
tokenize only the description portion after the prefix, and correct
all test assertions to match actual rendered column positions.

* feat(textobj): add debug mode, rename priority view buffer

Problem: the ]] motion reportedly lands one line past the header in
some environments, and ]t/[t may not override Neovim defaults. No
way to diagnose these at runtime. Also, pending://priority is a poor
buffer name for the flat ranked view.

Solution: add a debug config option (vim.g.pending = { debug = true })
that logs meta state, cursor positions, and mapping registration to
:messages at DEBUG level. Rename the buffer from pending://priority to
pending://queue. Internal view identifier stays 'priority'.

* docs: text objects, motions, debug mode, queue view rename

Problem: vimdoc had no documentation for the new text objects, motions,
debug config, or the pending://queue buffer rename.

Solution: add text object and motion tables to the mappings section,
document all eight <Plug> mappings, add debug field to the config
reference, update config example with new keymap defaults, rename
priority view references to queue throughout the vimdoc.

* fix(textobj): use correct config variable, raise log level

Problem: motion keymaps (]], [[, ]t, [t) were never set because
`config.get().debug` referenced an undefined `config` variable,
crashing _setup_buf_mappings before the motion loop. Debug logging
also used vim.log.levels.DEBUG which is filtered by default.

Solution: replace `config` with `cfg` (already in scope) and raise
both debug notify calls from DEBUG to INFO.

* ci: formt

lua/pending/config.lua

@@ -11,6 +11,14 @@
 ---@field undo? string|false
 ---@field open_line? string|false
 ---@field open_line_above? string|false
+---@field a_task? string|false
+---@field i_task? string|false
+---@field a_category? string|false
+---@field i_category? string|false
+---@field next_header? string|false
+---@field prev_header? string|false
+---@field next_task? string|false
+---@field prev_task? string|false
 
 ---@class pending.Config
 ---@field data_path string
@@ -22,6 +30,7 @@
 ---@field someday_date string
 ---@field category_order? string[]
 ---@field drawer_height? integer
+---@field debug? boolean
 ---@field keymaps pending.Keymaps
 ---@field gcal? pending.GcalConfig
 
@@ -47,6 +56,14 @@ local defaults = {
     undo = 'U',
     open_line = 'o',
     open_line_above = 'O',
+    a_task = 'at',
+    i_task = 'it',
+    a_category = 'aC',
+    i_category = 'iC',
+    next_header = ']]',
+    prev_header = '[[',
+    next_task = ']t',
+    prev_task = '[t',
   },
 }