Initial Aurora Core 0.1 implementation

Production-grade media metadata backend per docs/aurora-core-spec.md:
Aurora-owned UUIDv7 identity system, normalized movie/TV/people/credits
schema, provider abstraction with a TMDb adapter, an idempotent async
ingestion pipeline (normalize -> match -> upsert -> provenance), a
Postgres FTS/trigram search layer, a stateless FastAPI v1 API with
Redis caching/rate-limiting, arq workers, dev/prod Docker Compose
topologies, unit + integration + load tests, CI, and architecture/
database/API/ERD documentation.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

app/core/config.py

@@ -0,0 +1,103 @@
+"""Environment-based application configuration.
+
+All runtime configuration flows through this module. Nothing else in the
+codebase should read `os.environ` directly, so that configuration stays
+auditable and testable in one place.
+"""
+
+from __future__ import annotations
+
+from functools import lru_cache
+
+from pydantic import Field, field_validator
+from pydantic_settings import BaseSettings, SettingsConfigDict
+
+
+class Settings(BaseSettings):
+    model_config = SettingsConfigDict(
+        env_file=".env",
+        env_file_encoding="utf-8",
+        case_sensitive=False,
+        extra="ignore",
+    )
+
+    # --- Runtime ---
+    AURORA_ENV: str = Field(default="development")
+    AURORA_LOG_LEVEL: str = Field(default="INFO")
+    AURORA_API_DOCS_ENABLED: bool = Field(default=True)
+
+    # --- Database ---
+    DATABASE_URL: str = Field(
+        default="postgresql+asyncpg://aurora:aurora@localhost:5432/aurora_core"
+    )
+    DATABASE_URL_SYNC: str = Field(
+        default="postgresql+psycopg2://aurora:aurora@localhost:5432/aurora_core"
+    )
+    DATABASE_POOL_SIZE: int = Field(default=10)
+    DATABASE_MAX_OVERFLOW: int = Field(default=20)
+    # Set true when DATABASE_URL points at PgBouncer in transaction pooling
+    # mode (docker-compose.prod.yml): asyncpg's server-side prepared
+    # statements don't survive connections being handed to different clients
+    # between transactions, so they must be disabled.
+    DATABASE_BEHIND_TRANSACTION_POOLER: bool = Field(default=False)
+
+    # --- Redis ---
+    REDIS_URL: str = Field(default="redis://localhost:6379/0")
+    REDIS_REQUIRED: bool = Field(default=False)
+
+    # --- Security ---
+    AURORA_SECRET_KEY: str = Field(default="changeme-generate-a-real-secret")
+    AURORA_ADMIN_API_KEYS: str = Field(default="")
+
+    # --- CORS ---
+    CORS_ORIGINS: str = Field(default="http://localhost:3000")
+
+    # --- Providers ---
+    TMDB_API_KEY: str = Field(default="")
+
+    # --- Workers ---
+    WORKER_CONCURRENCY: int = Field(default=4)
+
+    # --- Caching ---
+    CACHE_DEFAULT_TTL: int = Field(default=300)
+
+    # --- Rate limiting ---
+    RATE_LIMIT_ENABLED: bool = Field(default=True)
+    RATE_LIMIT_PER_MINUTE: int = Field(default=120)
+
+    @field_validator("AURORA_ENV")
+    @classmethod
+    def _validate_env(cls, v: str) -> str:
+        allowed = {"development", "test", "staging", "production"}
+        if v not in allowed:
+            raise ValueError(f"AURORA_ENV must be one of {allowed}, got {v!r}")
+        return v
+
+    @property
+    def cors_origins_list(self) -> list[str]:
+        return [origin.strip() for origin in self.CORS_ORIGINS.split(",") if origin.strip()]
+
+    @property
+    def admin_api_keys_set(self) -> set[str]:
+        return {key.strip() for key in self.AURORA_ADMIN_API_KEYS.split(",") if key.strip()}
+
+    @property
+    def is_production(self) -> bool:
+        return self.AURORA_ENV == "production"
+
+    @property
+    def docs_url(self) -> str | None:
+        if not self.AURORA_API_DOCS_ENABLED:
+            return None
+        return "/docs"
+
+    @property
+    def openapi_url(self) -> str | None:
+        if not self.AURORA_API_DOCS_ENABLED:
+            return None
+        return "/openapi.json"
+
+
+@lru_cache
+def get_settings() -> Settings:
+    return Settings()