Improve LLM client immutability and CI model defaults. (#9)

Replace mutable Ollama model export with a const fallback and initializeModel return value, resolving the model from the environment after optional API discovery. Use a for-of loop over attempt indices instead of let in the retry path.

Continue PDF generation when map image generation or upscaling fails, and avoid mutating request headers in place.

Document Open WebUI-style URLs in the README, pin OLLAMA_MODEL in the Gitea release workflow, and adjust integration and unit tests for the new initialization behavior.

Reviewed-on: #9
Co-authored-by: keligrubb <keligrubb324@gmail.com>
Co-committed-by: keligrubb <keligrubb324@gmail.com>

src/imageGenerator.js

@@ -2,7 +2,7 @@ import sharp from 'sharp';
 import path from "path";
 import { mkdir, writeFile } from "fs/promises";
 import { fileURLToPath } from "url";
-import { callOllama, OLLAMA_MODEL } from "./ollamaClient.js";
+import { callOllama } from "./ollamaClient.js";
 
 const COMFYUI_ENABLED = process.env.COMFYUI_ENABLED !== 'false';
 const __dirname = path.dirname(fileURLToPath(import.meta.url));
@@ -63,7 +63,7 @@ Input:
 ${flavor}
 
 Output:`,
-    OLLAMA_MODEL,
+    undefined,
     3,
     "Generate Visual Prompt"
   );
@@ -239,22 +239,22 @@ export async function generateDungeonImages({ flavor }) {
     return path.join(__dirname, "dungeon_upscaled.png");
   }
 
-  const finalPrompt = await generateVisualPrompt(flavor);
-  console.log("Engineered visual prompt:\n", finalPrompt);
+  try {
+    const finalPrompt = await generateVisualPrompt(flavor);
+    console.log("Engineered visual prompt:\n", finalPrompt);
 
-  const baseFilename = `dungeon.png`;
-  const upscaledFilename = `dungeon_upscaled.png`;
+    const baseFilename = `dungeon.png`;
+    const upscaledFilename = `dungeon_upscaled.png`;
 
-  const filepath = await generateImageViaComfyUI(finalPrompt, baseFilename);
-  if (!filepath) {
-    throw new Error("Failed to generate dungeon image.");
+    const filepath = await generateImageViaComfyUI(finalPrompt, baseFilename);
+    if (!filepath) return null;
+
+    const upscaledPath = await upscaleImage(filepath, upscaledFilename, 1456, 1024);
+    if (!upscaledPath) return null;
+
+    return upscaledPath;
+  } catch (err) {
+    console.warn("Map image failed:", err.message);
+    return null;
   }
-
-  // Upscale 2x (half of A4 at 300dpi)
-  const upscaledPath = await upscaleImage(filepath, upscaledFilename, 1456, 1024);
-  if (!upscaledPath) {
-    throw new Error("Failed to upscale dungeon image.");
-  }
-
-  return upscaledPath;
 }