Add optional namespace field to tasks

Tasks can now be associated with specific namespaces in the monorepo:
- Added taskNamespace (Maybe Text) field to Task data type - Updated
createTask to accept optional namespace parameter - Added --namespace
CLI option to task create command - Display namespace in task list
output (e.g., [Omni/Task]) - Updated tests to pass Nothing for
namespace - Updated AGENTS.md documentation

Example usage:
  task create "Fix bug" project --namespace="Omni/Task"

Completed task: t-j0k1L2

Amp-Thread-ID:
https://ampcode.com/threads/T-85f4ee29-a529-4f59-ac6f-6ffec75b6a56
Co-authored-by: Amp <amp@ampcode.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/AGENTS.md b/AGENTS.md
index 9450a0a..dde7e67 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -14,15 +14,18 @@ The task manager is a dependency-aware issue tracker inspired by beads. It uses:
 
 ### Create a Task
 ```bash
-task create "<title>" <project> [--deps=<ids>]
+task create "<title>" <project> [--deps=<ids>] [--namespace=<ns>]
 ```
 
 Examples:
 ```bash
 task create "Add authentication" auth-system
-task create "Write tests" auth-system --deps=t-20241108120000
+task create "Write tests" auth-system --deps=t-a1b2c3
+task create "Fix type errors" task-manager --namespace="Omni/Task"
 ```
 
+The `--namespace` option associates the task with a specific namespace in the monorepo (e.g., `Omni/Task`, `Biz/Cloud`). This helps organize tasks by the code they relate to.
+
 ### List Tasks
 ```bash
 task list [--project=<project>]