feat(F.14): Unified Task System — F-TASK-MODEL/API/AGENT/WORK/UI/MIG/GOAL/TEST

- F-TASK-MODEL: Extended Task model with polymorphic assignee/entity/creator, subtasks, dependencies, task_type, success_criteria, progress
- F-TASK-API: Extended task routes with polymorphic filters, subtasks, dependencies, new lifecycle
- F-TASK-AGENT: ai_tools.py (191 lines) — create_task, assign_task, update_task_status, decompose_goal tools
- F-TASK-WORK: workstream.py — task_card and goal_card blocks in communication system
- F-TASK-UI: TaskBoard.tsx, TaskDetail.tsx, GoalView.tsx frontend components
- F-TASK-MIG: Migration 0124 — new columns, data migration for contact_id/assigned_to
- F-TASK-GOAL: Progress aggregation, success criteria evaluation, parent status propagation
- F-TASK-TEST: test_unified_tasks.py (414 lines)
- i18n updates for task system

alembic/versions/0124_unified_task_system.py

@@ -0,0 +1,114 @@
+"""Unified Task System (F.14).
+
+Adds polymorphic assignment/entity/creator fields, subtasks, dependencies,
+goals/milestones and agent-subtask support to the tasks table. Migrates
+legacy ``contact_id``/``assigned_to`` values into the polymorphic fields and
+migrates existing ``agent_subtasks`` rows into tasks with
+``task_type='agent_subtask'``.
+
+Revision ID: 0124
+Revises: 0123
+"""
+
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects.postgresql import JSONB, UUID as PGUUID
+
+revision = "0124"
+down_revision = "0123"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    # ── Add new columns to tasks ────────────────────────────────────────────
+    op.add_column("tasks", sa.Column("assignee_type", sa.String(20), nullable=False, server_default="user"))
+    op.add_column("tasks", sa.Column("assignee_id", PGUUID(as_uuid=True), nullable=True))
+    op.add_column("tasks", sa.Column("entity_type", sa.String(80), nullable=True))
+    op.add_column("tasks", sa.Column("entity_id", PGUUID(as_uuid=True), nullable=True))
+    op.add_column("tasks", sa.Column("creator_type", sa.String(20), nullable=False, server_default="user"))
+    op.add_column("tasks", sa.Column("creator_id", PGUUID(as_uuid=True), nullable=True))
+    op.add_column("tasks", sa.Column("parent_task_id", PGUUID(as_uuid=True), nullable=True))
+    op.add_column("tasks", sa.Column("depends_on", JSONB, nullable=False, server_default=sa.text("'[]'::jsonb")))
+    op.add_column("tasks", sa.Column("task_type", sa.String(30), nullable=False, server_default="todo"))
+    op.add_column("tasks", sa.Column("success_criteria", JSONB, nullable=True))
+    op.add_column("tasks", sa.Column("target_date", sa.DateTime(timezone=True), nullable=True))
+    op.add_column("tasks", sa.Column("progress", sa.Integer(), nullable=False, server_default="0"))
+
+    # ── Migrate legacy data into polymorphic fields ─────────────────────────
+    # contact_id → entity_type='contact' + entity_id
+    op.execute(
+        """
+        UPDATE tasks
+        SET entity_type = 'contact', entity_id = contact_id
+        WHERE contact_id IS NOT NULL AND entity_type IS NULL
+        """
+    )
+    # assigned_to → assignee_type='user' + assignee_id
+    op.execute(
+        """
+        UPDATE tasks
+        SET assignee_type = 'user', assignee_id = assigned_to
+        WHERE assigned_to IS NOT NULL AND assignee_id IS NULL
+        """
+    )
+    # created_by → creator_type='user' + creator_id
+    op.execute(
+        """
+        UPDATE tasks
+        SET creator_type = 'user', creator_id = created_by
+        WHERE created_by IS NOT NULL AND creator_id IS NULL
+        """
+    )
+
+    # ── Migrate AgentSubtask rows into tasks ────────────────────────────────
+    op.execute(
+        """
+        INSERT INTO tasks (
+            id, tenant_id, title, description, status, priority,
+            assignee_type, assignee_id, entity_type, entity_id,
+            creator_type, creator_id, task_type, depends_on, progress,
+            created_at, updated_at
+        )
+        SELECT
+            asub.id, asub.tenant_id,
+            asub.task_description, asub.task_description, asub.status, 'medium',
+            'agent', asub.child_agent_id, 'agent', asub.parent_agent_id,
+            'agent', asub.parent_agent_id, 'agent_subtask', '[]'::jsonb, 0,
+            asub.created_at, asub.updated_at
+        FROM agent_subtasks asub
+        WHERE NOT EXISTS (
+            SELECT 1 FROM tasks t WHERE t.id = asub.id
+        )
+        """
+    )
+
+    # ── Indexes ─────────────────────────────────────────────────────────────
+    op.create_index("ix_tasks_tenant_entity", "tasks", ["tenant_id", "entity_type", "entity_id"])
+    op.create_index("ix_tasks_tenant_assignee", "tasks", ["tenant_id", "assignee_type", "assignee_id"])
+    op.create_index("ix_tasks_tenant_parent", "tasks", ["tenant_id", "parent_task_id"])
+    op.create_index("ix_tasks_tenant_type", "tasks", ["tenant_id", "task_type"])
+    op.create_foreign_key(
+        "fk_tasks_parent_task_id", "tasks", "tasks", ["parent_task_id"], ["id"],
+        ondelete="CASCADE",
+    )
+
+
+def downgrade() -> None:
+    op.drop_constraint("fk_tasks_parent_task_id", "tasks", type_="foreignkey")
+    op.drop_index("ix_tasks_tenant_type", table_name="tasks")
+    op.drop_index("ix_tasks_tenant_parent", table_name="tasks")
+    op.drop_index("ix_tasks_tenant_assignee", table_name="tasks")
+    op.drop_index("ix_tasks_tenant_entity", table_name="tasks")
+    op.drop_column("tasks", "progress")
+    op.drop_column("tasks", "target_date")
+    op.drop_column("tasks", "success_criteria")
+    op.drop_column("tasks", "task_type")
+    op.drop_column("tasks", "depends_on")
+    op.drop_column("tasks", "parent_task_id")
+    op.drop_column("tasks", "creator_id")
+    op.drop_column("tasks", "creator_type")
+    op.drop_column("tasks", "entity_id")
+    op.drop_column("tasks", "entity_type")
+    op.drop_column("tasks", "assignee_id")
+    op.drop_column("tasks", "assignee_type")