Add Fireworks to LlamaIndex (#539)

.changeset/tender-kiwis-unite.md

README.md

apps/docs/docs/modules/llms/available_llms/fireworks.md

examples/readers/src/pdf_fw.ts

examples/readers/src/pdf_fw_openai.ts

examples/readers/test.py

packages/core/src/embeddings/fireworks.ts

packages/core/src/embeddings/index.ts

packages/core/src/llm/fireworks.ts

packages/core/src/llm/index.ts

packages/eslint-config-custom/index.js