ci: add pytest and ruff linting to CI, fix all lint errors

- Add test job to build.yaml that runs pytest and ruff before building images
- Add standalone test.yaml workflow for PRs
- Add ruff.toml with E/F/I rules configured
- Fix all ruff lint errors: sort imports, remove unused imports, fix re-exports
- Build jobs now depend on test job passing (needs: test)

Closes leeworks-agents/SPARC#18
Closes leeworks-agents/SPARC#19

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

SPARC/__init__.py

@@ -1,3 +1,4 @@
-from .types import Patents, Patent
+from .types import Patent as Patent
+from .types import Patents as Patents
 
-all = ["Patents", "Patent"]
+__all__ = ["Patents", "Patent"]

SPARC/analyzer.py

@@ -13,9 +13,9 @@ from SPARC import config
 
 logger = logging.getLogger(__name__)
 from SPARC.database import DatabaseClient
-from SPARC.serp_api import SERP
 from SPARC.llm import LLMAnalyzer
-from SPARC.types import Patent, Patents, CompanyAnalysisResult, BatchAnalysisResult
+from SPARC.serp_api import SERP
+from SPARC.types import BatchAnalysisResult, CompanyAnalysisResult, Patent, Patents
 
 
 class CompanyAnalyzer:

SPARC/database.py

@@ -1,14 +1,15 @@
 """Database client for storing and retrieving LLM messages and user authentication."""
 
 import contextlib
-import psycopg2
-from psycopg2.pool import ThreadedConnectionPool
-from psycopg2.extras import RealDictCursor
-from typing import Dict, List, Optional
-from datetime import datetime, timedelta
-import json
 import hashlib
+import json
+from datetime import datetime, timedelta
+from typing import Dict, List, Optional
+
 import bcrypt
+import psycopg2
+from psycopg2.extras import RealDictCursor
+from psycopg2.pool import ThreadedConnectionPool
 
 
 class DatabaseClient:

SPARC/serp_api.py

@@ -1,12 +1,15 @@
 import os
-import serpapi
-from SPARC import config
 import re
-import pdfplumber  # pip install pdfplumber
-import requests
 from datetime import datetime, timedelta
 from typing import Dict
-from SPARC.types import Patents, Patent
+
+import pdfplumber  # pip install pdfplumber
+import requests
+import serpapi
+
+from SPARC import config
+from SPARC.types import Patent, Patents
+
 
 class SERP:
   def query(company: str, days_back: int = None) -> Patents: