feat(api): add memoir image prompt settings and optimization service

Made-with: Cursor

api/services/memoir_images/settings.py

@@ -0,0 +1,25 @@
+import os
+from dataclasses import dataclass
+
+
+@dataclass(frozen=True)
+class MemoirImageSettings:
+    enabled: bool
+    max_per_chapter: int
+    provider: str
+    default_style: str
+    default_size: str
+    poll_interval_seconds: int
+    max_attempts: int
+
+    @classmethod
+    def from_env(cls) -> "MemoirImageSettings":
+        return cls(
+            enabled=os.getenv("MEMOIR_IMAGE_ENABLED", "").lower() in {"1", "true", "yes"},
+            max_per_chapter=int(os.getenv("MEMOIR_IMAGE_MAX_PER_CHAPTER", "2")),
+            provider=os.getenv("MEMOIR_IMAGE_PROVIDER", "liblib"),
+            default_style=os.getenv("MEMOIR_IMAGE_STYLE_DEFAULT", "watercolor"),
+            default_size=os.getenv("MEMOIR_IMAGE_SIZE_DEFAULT", "1024x1024"),
+            poll_interval_seconds=int(os.getenv("MEMOIR_IMAGE_POLL_INTERVAL", "3")),
+            max_attempts=int(os.getenv("MEMOIR_IMAGE_MAX_ATTEMPTS", "20")),
+        )