Initial commit: scheduler service extraction from portainer-core

Extracted standalone scheduler service with:
- FastAPI REST API for task management
- APScheduler-based task execution
- PostgreSQL persistence
- Docker container support
- Gitea Actions CI/CD workflow

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

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

pytest.ini

@@ -0,0 +1,45 @@
+[pytest]
+# Pytest configuration for The Scheduler
+
+# Test discovery patterns
+python_files = test_*.py
+python_classes = Test*
+python_functions = test_*
+
+# Test paths
+testpaths = tests
+
+# Asyncio mode
+asyncio_mode = auto
+asyncio_default_fixture_loop_scope = function
+
+# Coverage options
+addopts =
+    --verbose
+    --strict-markers
+    --tb=short
+    --cov=src
+    --cov-report=term-missing
+    --cov-report=html:htmlcov
+    --cov-report=json:coverage.json
+    --cov-branch
+
+# Custom markers
+markers =
+    unit: Unit tests (fast, no external dependencies)
+    integration: Integration tests (may use database, slower)
+    executor: Tests for task executors
+    api: API endpoint tests
+    slow: Tests that take a while to run
+
+# Ignore patterns
+norecursedirs = .git .tox dist build *.egg venv __pycache__ node_modules
+
+# Console output
+console_output_style = progress
+
+# Fail on first error (disable for CI)
+# addopts = --exitfirst
+
+# Show local variables in tracebacks
+# addopts = --showlocals