feat(parse): expand date vocabulary with named dates

Problem: the date input only supports today, tomorrow, +Nd, and
weekday names, lacking relative offsets like weeks/months, period
boundaries, ordinals, month names, and backdating.

Solution: add yesterday, eod, sow/eow, som/eom, soq/eoq, soy/eoy,
+Nw, +Nm, -Nd, -Nw, ordinals (1st-31st), month names (jan-dec),
and later/someday to resolve_date(). Add tests for all new tokens.

lua/pending/parse.lua

@@ -39,14 +39,33 @@ local weekday_map = {
   sat = 7,
 }
 
+local month_map = {
+  jan = 1, feb = 2, mar = 3, apr = 4,
+  may = 5, jun = 6, jul = 7, aug = 8,
+  sep = 9, oct = 10, nov = 11, dec = 12,
+}
+
+---@param today osdate
+---@return string
+local function today_str(today)
+  return os.date('%Y-%m-%d', os.time({ year = today.year, month = today.month, day = today.day })) --[[@as string]]
+end
+
 ---@param text string
 ---@return string|nil
 function M.resolve_date(text)
   local lower = text:lower()
   local today = os.date('*t') --[[@as osdate]]
 
-  if lower == 'today' then
-    return os.date('%Y-%m-%d', os.time({ year = today.year, month = today.month, day = today.day })) --[[@as string]]
+  if lower == 'today' or lower == 'eod' then
+    return today_str(today)
+  end
+
+  if lower == 'yesterday' then
+    return os.date(
+      '%Y-%m-%d',
+      os.time({ year = today.year, month = today.month, day = today.day - 1 })
+    ) --[[@as string]]
   end
 
   if lower == 'tomorrow' then
@@ -56,6 +75,72 @@ function M.resolve_date(text)
     ) --[[@as string]]
   end
 
+  if lower == 'sow' then
+    local delta = -((today.wday - 2) % 7)
+    return os.date(
+      '%Y-%m-%d',
+      os.time({ year = today.year, month = today.month, day = today.day + delta })
+    ) --[[@as string]]
+  end
+
+  if lower == 'eow' then
+    local delta = (1 - today.wday) % 7
+    return os.date(
+      '%Y-%m-%d',
+      os.time({ year = today.year, month = today.month, day = today.day + delta })
+    ) --[[@as string]]
+  end
+
+  if lower == 'som' then
+    return os.date(
+      '%Y-%m-%d',
+      os.time({ year = today.year, month = today.month, day = 1 })
+    ) --[[@as string]]
+  end
+
+  if lower == 'eom' then
+    return os.date(
+      '%Y-%m-%d',
+      os.time({ year = today.year, month = today.month + 1, day = 0 })
+    ) --[[@as string]]
+  end
+
+  if lower == 'soq' then
+    local q = math.ceil(today.month / 3)
+    local first_month = (q - 1) * 3 + 1
+    return os.date(
+      '%Y-%m-%d',
+      os.time({ year = today.year, month = first_month, day = 1 })
+    ) --[[@as string]]
+  end
+
+  if lower == 'eoq' then
+    local q = math.ceil(today.month / 3)
+    local last_month = q * 3
+    return os.date(
+      '%Y-%m-%d',
+      os.time({ year = today.year, month = last_month + 1, day = 0 })
+    ) --[[@as string]]
+  end
+
+  if lower == 'soy' then
+    return os.date(
+      '%Y-%m-%d',
+      os.time({ year = today.year, month = 1, day = 1 })
+    ) --[[@as string]]
+  end
+
+  if lower == 'eoy' then
+    return os.date(
+      '%Y-%m-%d',
+      os.time({ year = today.year, month = 12, day = 31 })
+    ) --[[@as string]]
+  end
+
+  if lower == 'later' or lower == 'someday' then
+    return config.get().someday_date
+  end
+
   local n = lower:match('^%+(%d+)d$')
   if n then
     return os.date(
@@ -63,13 +148,102 @@ function M.resolve_date(text)
       os.time({
         year = today.year,
         month = today.month,
-        day = today.day + (
-            tonumber(n) --[[@as integer]]
-          ),
+        day = today.day + (tonumber(n) --[[@as integer]]),
       })
     ) --[[@as string]]
   end
 
+  n = lower:match('^%+(%d+)w$')
+  if n then
+    return os.date(
+      '%Y-%m-%d',
+      os.time({
+        year = today.year,
+        month = today.month,
+        day = today.day + (tonumber(n) --[[@as integer]]) * 7,
+      })
+    ) --[[@as string]]
+  end
+
+  n = lower:match('^%+(%d+)m$')
+  if n then
+    return os.date(
+      '%Y-%m-%d',
+      os.time({
+        year = today.year,
+        month = today.month + (tonumber(n) --[[@as integer]]),
+        day = today.day,
+      })
+    ) --[[@as string]]
+  end
+
+  n = lower:match('^%-(%d+)d$')
+  if n then
+    return os.date(
+      '%Y-%m-%d',
+      os.time({
+        year = today.year,
+        month = today.month,
+        day = today.day - (tonumber(n) --[[@as integer]]),
+      })
+    ) --[[@as string]]
+  end
+
+  n = lower:match('^%-(%d+)w$')
+  if n then
+    return os.date(
+      '%Y-%m-%d',
+      os.time({
+        year = today.year,
+        month = today.month,
+        day = today.day - (tonumber(n) --[[@as integer]]) * 7,
+      })
+    ) --[[@as string]]
+  end
+
+  local ord = lower:match('^(%d+)[snrt][tdh]$')
+  if ord then
+    local day_num = tonumber(ord) --[[@as integer]]
+    if day_num >= 1 and day_num <= 31 then
+      local m, y = today.month, today.year
+      if today.day >= day_num then
+        m = m + 1
+        if m > 12 then
+          m = 1
+          y = y + 1
+        end
+      end
+      local t = os.time({ year = y, month = m, day = day_num })
+      local check = os.date('*t', t) --[[@as osdate]]
+      if check.day == day_num then
+        return os.date('%Y-%m-%d', t) --[[@as string]]
+      end
+      m = m + 1
+      if m > 12 then
+        m = 1
+        y = y + 1
+      end
+      t = os.time({ year = y, month = m, day = day_num })
+      check = os.date('*t', t) --[[@as osdate]]
+      if check.day == day_num then
+        return os.date('%Y-%m-%d', t) --[[@as string]]
+      end
+      return nil
+    end
+  end
+
+  local target_month = month_map[lower]
+  if target_month then
+    local y = today.year
+    if today.month >= target_month then
+      y = y + 1
+    end
+    return os.date(
+      '%Y-%m-%d',
+      os.time({ year = y, month = target_month, day = 1 })
+    ) --[[@as string]]
+  end
+
   local target_wday = weekday_map[lower]
   if target_wday then
     local current_wday = today.wday