Add enhanced filtering to task list command

Implement --status and --namespace filters for task list:

New filters: - --status: Filter by open, in-progress, or done -
--namespace: Filter by namespace (e.g., Omni/Task)

All filters can be combined: - task list --parent=t-abc123
--status=open - task list --type=epic --status=done - task list
--namespace="Omni/Task" --status=open

Updated listTasks signature to accept all filter parameters and apply
them in sequence. Updated AGENTS.md with examples.

Closes task t-PpZGVf

1 files changed, 9 insertions, 4 deletions

diff --git a/Omni/Task/Core.hs b/Omni/Task/Core.hs
index 6285ef7..140d7dc 100644
--- a/Omni/Task/Core.hs
+++ b/Omni/Task/Core.hs
@@ -5,7 +5,6 @@
 module Omni.Task.Core where
 
 import Alpha
-import Control.Monad ((>>=))
 import Data.Aeson (FromJSON, ToJSON, decode, encode)
 import qualified Data.Aeson as Aeson
 import qualified Data.Aeson.KeyMap as KM
@@ -210,20 +209,26 @@ updateTaskStatus tid newStatus = do
   TIO.writeFile tasksFile ""
   traverse_ saveTask updatedTasks
 
--- List tasks, optionally filtered by type or parent
-listTasks :: Maybe TaskType -> Maybe Text -> IO [Task]
-listTasks maybeType maybeParent = do
+-- List tasks, optionally filtered by type, parent, status, or namespace
+listTasks :: Maybe TaskType -> Maybe Text -> Maybe Status -> Maybe Text -> IO [Task]
+listTasks maybeType maybeParent maybeStatus maybeNamespace = do
   tasks <- loadTasks
   let filtered =
         tasks
           |> filterByType maybeType
           |> filterByParent maybeParent
+          |> filterByStatus maybeStatus
+          |> filterByNamespace maybeNamespace
   pure filtered
   where
     filterByType Nothing ts = ts
     filterByType (Just typ) ts = filter (\t -> taskType t == typ) ts
     filterByParent Nothing ts = ts
     filterByParent (Just pid) ts = filter (\t -> taskParent t == Just pid) ts
+    filterByStatus Nothing ts = ts
+    filterByStatus (Just status) ts = filter (\t -> taskStatus t == status) ts
+    filterByNamespace Nothing ts = ts
+    filterByNamespace (Just ns) ts = filter (\t -> taskNamespace t == Just ns) ts
 
 -- Get ready tasks (not blocked by dependencies)
 getReadyTasks :: IO [Task]