Add fal.ai Provider Support

[rbur0425]

Add fal.ai Provider Support with Expanded Model Catalog

This PR adds full fal.ai integration as a second generation provider alongside the existing
muapi.ai backend, with a shared model picker UI and a significantly expanded model catalog.

---

What's new

fal.ai API client (packages/studio/src/fal.js)

• Submit/poll generation loop against queue.fal.run
• File upload via fal storage
• Balance fetching
• Handles both image and video generation, lip sync, and image-to-image

Unified studio client (packages/studio/src/studioClient.js)

• Single generate() entry point that routes to fal or muapi based on the model's provider field
• Aspect ratio → fal image_size conversion
• fal LoRA payload mapping

Shared ModelDropdown component (packages/studio/src/components/ModelDropdown.jsx)

• Replaces per-studio inline dropdowns across Image, Video, Lip Sync, and Cinema studios
• Grouped by provider (fal.ai / muapi.ai) with count badges
• Live search across 150+ models by name or ID
• Recently used models tracked in localStorage

Expanded model catalog (packages/studio/src/models.js)

• 34 fal.ai text-to-image models added, including:
  • Nano Banana / Nano Banana Pro / Nano Banana 2 (Gemini 2.5 Flash / 3 Pro / 3.1 Flash)
  • Imagen 4 / Fast / Ultra
  • FLUX1.1 [pro] Ultra, FLUX.1 Kontext [pro/max]
  • Flux 2 [dev / Turbo / Flash / Max / Pro]
  • Ideogram V2 / V3, Recraft V4 / Pro
  • GPT-Image 1.5, Qwen Image 2, Seedream v4 / v4.5
  • Kling Image v3, MiniMax Image, Luma Photon, SD 3.5 Large, HiDream I1, Z-Image Turbo / Base
• 9 fal.ai image-to-image models (schema-verified to accept image input)
• fal LoRA represented as a single real fal-ai/flux-lora entry with runtime loras payload, not
  fabricated catalog variants

API key management

• ApiKeyModal and StandaloneShell updated to accept and store a separate fal_key alongside
  muapi_key

Bug fixes

• LipSync Studio: missing dropdownRef declaration caused a runtime crash when opening the model
  picker — fixed
• Cinema Studio: history card click now opens fullscreen preview; restore-settings is a
  separate explicit action

New components

• GeneratingState — shared loading state UI used across studios
• ProviderBalance — displays live balance for the active provider

[rbur0425]

@Anil-matcha why did you close this?