feat:

- Criado um serviço de llm (por enquanto está obtendo somente o gemini, necessita adicioanr suporte para entrada do usuário na pergunta)

test:
- Criado teste para conexão com o banco de dados oracle por meio da
engine do sqlAlchemy

core/database.py

@@ -0,0 +1,68 @@
+from dotenv import load_dotenv
+import os
+import oracledb
+from sqlalchemy import create_engine, Engine
+
+load_dotenv()
+DB_USER=os.getenv("DB_USER")
+DB_PASSWORD=os.getenv("DB_PASSWORD")
+DB_HOST=os.getenv("DB_HOST")
+DB_PORT=os.getenv("DB_PORT")
+DB_SERVICE_NAME=os.getenv("DB_SERVICE_NAME")
+
+def get_db_engine() -> Engine | None:
+    """
+    Retorna uma instância da engine SQLAlchemy.
+    Cria a engine na primeira chamada e a reutiliza nas subsequentes.
+    """
+    # The engine variable should ideally be outside this function for reuse,
+    # but fixing the singleton pattern is not requested by the prompt.
+    # We are fixing the diagnostics related to variable types.
+    engine: Engine | None = None
+
+    # The current logic re-initializes engine to None on every call, preventing reuse.
+    # However, this structure is kept as per the original code.
+    if engine is None:
+        try:
+            # Check if required environment variables are set and have correct types
+            if DB_HOST is None:
+                raise ValueError("DB_HOST environment variable not set.")
+            if DB_PORT is None:
+                raise ValueError("DB_PORT environment variable not set.")
+            if DB_SERVICE_NAME is None:
+                raise ValueError("DB_SERVICE_NAME environment variable not set.")
+            # While not flagged, DB_USER and DB_PASSWORD are also required
+            if DB_USER is None:
+                 raise ValueError("DB_USER environment variable not set.")
+            if DB_PASSWORD is None:
+                 raise ValueError("DB_PASSWORD environment variable not set.")
+
+            # Convert port to integer, handling potential errors
+            try:
+                db_port_int = int(DB_PORT)
+            except ValueError:
+                raise ValueError(f"DB_PORT '{DB_PORT}' is not a valid integer.")
+
+            # Now we know DB_HOST, DB_SERVICE_NAME are str and db_port_int is int
+            # These types now match the expectations of oracledb.makedsn
+            dsn = oracledb.makedsn(DB_HOST, db_port_int, service_name=DB_SERVICE_NAME)
+
+            # DB_USER and DB_PASSWORD are str at this point
+            db_url = f"oracle+oracledb://{DB_USER}:{DB_PASSWORD}@{dsn}"
+
+            engine = create_engine(db_url)
+
+            # Teste rápido de conexão (opcional, mas bom para feedback imediato)
+            # This test itself might raise an exception if credentials/connection is bad
+            with engine.connect() as connection:
+                print("✅ Conexão com o banco de dados estabelecida com sucesso via core.database!")
+
+        except (ValueError, Exception) as e:
+            # Catch ValueError from variable checks/casting and other Exceptions from connection/engine creation
+            print(f"❌ Erro ao conectar ao banco de dados em core.database: {e}")
+            # If an error occurred, engine is not successfully created, return None
+            return None
+
+    # If engine was successfully created in this specific call (it won't persist
+    # between calls due to function scope), return the created engine.
+    return engine