feat(backend): Add Syndarix domain models with CRUD operations

- Add Project model with slug, description, autonomy level, and settings
- Add AgentType model for agent templates with model config and failover
- Add AgentInstance model for running agents with status and memory
- Add Issue model with external tracker sync (Gitea/GitHub/GitLab)
- Add Sprint model with velocity tracking and lifecycle management
- Add comprehensive Pydantic schemas with validation
- Add full CRUD operations for all models with filtering/sorting
- Add 280+ tests for models, schemas, and CRUD operations

Implements #23, #24, #25, #26, #27

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/tests/schemas/syndarix/test_agent_instance_schemas.py

@@ -0,0 +1,244 @@
+# tests/schemas/syndarix/test_agent_instance_schemas.py
+"""
+Tests for AgentInstance schema validation.
+"""
+
+import uuid
+from decimal import Decimal
+
+import pytest
+from pydantic import ValidationError
+
+from app.schemas.syndarix import (
+    AgentInstanceCreate,
+    AgentInstanceUpdate,
+    AgentStatus,
+)
+
+
+class TestAgentInstanceCreateValidation:
+    """Tests for AgentInstanceCreate schema validation."""
+
+    def test_valid_agent_instance_create(self, valid_agent_instance_data):
+        """Test creating agent instance with valid data."""
+        instance = AgentInstanceCreate(**valid_agent_instance_data)
+
+        assert instance.agent_type_id is not None
+        assert instance.project_id is not None
+
+    def test_agent_instance_create_defaults(self, valid_agent_instance_data):
+        """Test that defaults are applied correctly."""
+        instance = AgentInstanceCreate(**valid_agent_instance_data)
+
+        assert instance.status == AgentStatus.IDLE
+        assert instance.current_task is None
+        assert instance.short_term_memory == {}
+        assert instance.long_term_memory_ref is None
+        assert instance.session_id is None
+
+    def test_agent_instance_create_with_all_fields(self, valid_uuid):
+        """Test creating agent instance with all optional fields."""
+        instance = AgentInstanceCreate(
+            agent_type_id=valid_uuid,
+            project_id=valid_uuid,
+            status=AgentStatus.WORKING,
+            current_task="Processing feature request",
+            short_term_memory={"context": "working"},
+            long_term_memory_ref="project-123/agent-456",
+            session_id="session-abc",
+        )
+
+        assert instance.status == AgentStatus.WORKING
+        assert instance.current_task == "Processing feature request"
+        assert instance.short_term_memory == {"context": "working"}
+        assert instance.long_term_memory_ref == "project-123/agent-456"
+        assert instance.session_id == "session-abc"
+
+    def test_agent_instance_create_agent_type_id_required(self, valid_uuid):
+        """Test that agent_type_id is required."""
+        with pytest.raises(ValidationError) as exc_info:
+            AgentInstanceCreate(
+                project_id=valid_uuid,
+            )
+
+        errors = exc_info.value.errors()
+        assert any("agent_type_id" in str(e).lower() for e in errors)
+
+    def test_agent_instance_create_project_id_required(self, valid_uuid):
+        """Test that project_id is required."""
+        with pytest.raises(ValidationError) as exc_info:
+            AgentInstanceCreate(
+                agent_type_id=valid_uuid,
+            )
+
+        errors = exc_info.value.errors()
+        assert any("project_id" in str(e).lower() for e in errors)
+
+
+class TestAgentInstanceUpdateValidation:
+    """Tests for AgentInstanceUpdate schema validation."""
+
+    def test_agent_instance_update_partial(self):
+        """Test updating only some fields."""
+        update = AgentInstanceUpdate(
+            status=AgentStatus.WORKING,
+        )
+
+        assert update.status == AgentStatus.WORKING
+        assert update.current_task is None
+        assert update.short_term_memory is None
+
+    def test_agent_instance_update_all_fields(self):
+        """Test updating all fields."""
+        from datetime import UTC, datetime
+
+        now = datetime.now(UTC)
+        update = AgentInstanceUpdate(
+            status=AgentStatus.WORKING,
+            current_task="New task",
+            short_term_memory={"new": "context"},
+            long_term_memory_ref="new-ref",
+            session_id="new-session",
+            last_activity_at=now,
+            tasks_completed=5,
+            tokens_used=10000,
+            cost_incurred=Decimal("1.5000"),
+        )
+
+        assert update.status == AgentStatus.WORKING
+        assert update.current_task == "New task"
+        assert update.tasks_completed == 5
+        assert update.tokens_used == 10000
+        assert update.cost_incurred == Decimal("1.5000")
+
+    def test_agent_instance_update_tasks_completed_negative_fails(self):
+        """Test that negative tasks_completed raises ValidationError."""
+        with pytest.raises(ValidationError) as exc_info:
+            AgentInstanceUpdate(tasks_completed=-1)
+
+        errors = exc_info.value.errors()
+        assert any("tasks_completed" in str(e).lower() for e in errors)
+
+    def test_agent_instance_update_tokens_used_negative_fails(self):
+        """Test that negative tokens_used raises ValidationError."""
+        with pytest.raises(ValidationError) as exc_info:
+            AgentInstanceUpdate(tokens_used=-1)
+
+        errors = exc_info.value.errors()
+        assert any("tokens_used" in str(e).lower() for e in errors)
+
+    def test_agent_instance_update_cost_incurred_negative_fails(self):
+        """Test that negative cost_incurred raises ValidationError."""
+        with pytest.raises(ValidationError) as exc_info:
+            AgentInstanceUpdate(cost_incurred=Decimal("-0.01"))
+
+        errors = exc_info.value.errors()
+        assert any("cost_incurred" in str(e).lower() for e in errors)
+
+
+class TestAgentStatusEnum:
+    """Tests for AgentStatus enum validation."""
+
+    def test_valid_agent_statuses(self, valid_uuid):
+        """Test all valid agent statuses."""
+        for status in AgentStatus:
+            instance = AgentInstanceCreate(
+                agent_type_id=valid_uuid,
+                project_id=valid_uuid,
+                status=status,
+            )
+            assert instance.status == status
+
+    def test_invalid_agent_status(self, valid_uuid):
+        """Test that invalid agent status raises ValidationError."""
+        with pytest.raises(ValidationError):
+            AgentInstanceCreate(
+                agent_type_id=valid_uuid,
+                project_id=valid_uuid,
+                status="invalid",  # type: ignore
+            )
+
+
+class TestAgentInstanceShortTermMemory:
+    """Tests for AgentInstance short_term_memory validation."""
+
+    def test_short_term_memory_empty_dict(self, valid_uuid):
+        """Test that empty short_term_memory is valid."""
+        instance = AgentInstanceCreate(
+            agent_type_id=valid_uuid,
+            project_id=valid_uuid,
+            short_term_memory={},
+        )
+        assert instance.short_term_memory == {}
+
+    def test_short_term_memory_complex(self, valid_uuid):
+        """Test complex short_term_memory structure."""
+        memory = {
+            "conversation_history": [
+                {"role": "user", "content": "Hello"},
+                {"role": "assistant", "content": "Hi there"},
+            ],
+            "recent_files": ["file1.py", "file2.py"],
+            "decisions": {"key": "value"},
+            "context_tokens": 1024,
+        }
+        instance = AgentInstanceCreate(
+            agent_type_id=valid_uuid,
+            project_id=valid_uuid,
+            short_term_memory=memory,
+        )
+        assert instance.short_term_memory == memory
+
+
+class TestAgentInstanceStringFields:
+    """Tests for AgentInstance string field validation."""
+
+    def test_long_term_memory_ref_max_length(self, valid_uuid):
+        """Test long_term_memory_ref max length."""
+        long_ref = "a" * 500  # Max length is 500
+
+        instance = AgentInstanceCreate(
+            agent_type_id=valid_uuid,
+            project_id=valid_uuid,
+            long_term_memory_ref=long_ref,
+        )
+        assert instance.long_term_memory_ref == long_ref
+
+    def test_long_term_memory_ref_too_long(self, valid_uuid):
+        """Test that too long long_term_memory_ref raises ValidationError."""
+        too_long = "a" * 501
+
+        with pytest.raises(ValidationError) as exc_info:
+            AgentInstanceCreate(
+                agent_type_id=valid_uuid,
+                project_id=valid_uuid,
+                long_term_memory_ref=too_long,
+            )
+
+        errors = exc_info.value.errors()
+        assert any("long_term_memory_ref" in str(e).lower() for e in errors)
+
+    def test_session_id_max_length(self, valid_uuid):
+        """Test session_id max length."""
+        long_session = "a" * 255  # Max length is 255
+
+        instance = AgentInstanceCreate(
+            agent_type_id=valid_uuid,
+            project_id=valid_uuid,
+            session_id=long_session,
+        )
+        assert instance.session_id == long_session
+
+    def test_session_id_too_long(self, valid_uuid):
+        """Test that too long session_id raises ValidationError."""
+        too_long = "a" * 256
+
+        with pytest.raises(ValidationError) as exc_info:
+            AgentInstanceCreate(
+                agent_type_id=valid_uuid,
+                project_id=valid_uuid,
+                session_id=too_long,
+            )
+
+        errors = exc_info.value.errors()
+        assert any("session_id" in str(e).lower() for e in errors)