OpenRouter image-only generators should not request text output

[lyrishark]

OpenRouter image-only generators should not request text output

Summary

OpenRouter-backed image generators can fail for image-only model families such
as Flux even when GPT-image works through the same provider. The local Flux slot
used black-forest-labs/flux.2-max; the GPT slot used openai/gpt-5-image.
OpenRouter reports Flux as image-only output, while GPT-image supports both
image and text output.

Impact

• Flux/other image-only OpenRouter generators can return provider errors, seen
  locally as a 404, while GPT-image continues to succeed.
• This makes the Image Generation settings look healthy because both generator
  slots use OpenRouter and valid API credentials, but one request shape is not
  valid for the selected model family.

Root Cause

generateViaOpenRouter() always sent:

"modalities": ["image", "text"]

That is correct for text-capable image models such as openai/gpt-5-image, but
not for image-only families such as Flux. Those should request only:

"modalities": ["image"]

Local Patch

• Added OpenRouter model-family detection for known image-only families:
  Flux/Black Forest Labs, Sourceful, Recraft, Microsoft MAI Image, Grok Imagine,
  and Seedream.
• OpenRouter image-only families now send modalities: ["image"].
• Text-capable models such as GPT-image continue to send
  modalities: ["image", "text"].
• Normalized an accidentally pasted full
  https://openrouter.ai/api/v1/chat/completions URL back to the API base URL
  before appending /chat/completions, preventing a related doubled-path 404.
• Added generate_image_test.ts coverage for Flux, GPT-image, and full endpoint
  URL normalization.

Verification

• deno fmt --check packages/psycheros/src/tools/generate-image.ts packages/psycheros/tests/generate_image_test.ts
  passed.
• deno test -A --no-check packages/psycheros/tests/generate_image_test.ts
  passed (3 passed).
• Plain deno test -A packages/psycheros/tests/generate_image_test.ts is still
  blocked by pre-existing Windows timer type errors in unrelated modules:
  src/mcp-client/mod.ts and src/scheduler/scheduler.ts.

[lyrishark]

Local verification update: mirrored the patch into the installed AppData source, restarted the installed daemon on port 3000, confirmed the app serves '/', and ran a direct Flux smoke with the live saved Flux config. The safe prompt generated /generated-images/c118ea44-fe9a-421c-a8c7-7c95f7894fe5.png successfully.