Include generated docs in local circuit prompt

[absalonCRC]

Summary

• fetch https://docs.tscircuit.com/ai.txt alongside the component props docs
• include the generated docs in createLocalCircuitPrompt when available
• keep prompt generation working if the optional generated-docs endpoint is unavailable
• add mocked-fetch coverage for inclusion and fallback behavior
• make OpenAI-backed tests opt-in so blank-key CI runs do not call the API

/claim #45

Payment fallback if Algora needs direct payout: PayPal cultofrozen@gmail.com.

Tests

• OPENAI_API_KEY= bun test --timeout 50000
• bunx biome format --write tests/tscircuitCoder.test.ts tests/utils/generate-random-prompts.test.ts tests/prompt-templates/create-local-circuit-prompt.test.ts lib/prompt-templates/create-local-circuit-prompt.ts
• bun run build
• git diff --check