Make content agent testable for issue #5

[wangedmund77-cmyk]

Summary

• makes the content agent import-safe by moving Supabase client creation behind generateContent
• guards Deno.serve behind import.meta.main and exposes createContentAgentHandler() for tests
• adds helpers for bounty context formatting, tweet normalization, and guaranteed five-item thread output
• validates LLM HTTP responses and Supabase insert errors instead of silently accepting empty/failed output
• adds focused tests for context formatting, tweet trimming, separator parsing, fallback thread padding, and numbered LLM output

Acceptance criteria

• generateContent(bounty_id) still returns { tweet, thread, blog_post }
• tweet output is normalized and capped at 280 characters
• thread output is guaranteed to contain five entries
• content storage errors are surfaced
• tests cover mock content shaping without requiring live LLM credentials

Validation

• git diff --check
• Node smoke check confirmed the expected helper exports and guarded handler are present

Environment limits:

• Deno is not installed locally, so tests/content-agent.test.ts was added but not executed here.
• Plain tsc cannot resolve this repo’s Deno/JSR import (jsr:@supabase/supabase-js@2) or Deno globals without a Deno type environment.

Closes #5

Payment details can be provided through the repository-approved payout flow after merge.

[wangedmund77-cmyk]

Pushed a focused acceptance follow-up after comparing newer issue #5 content-agent submissions.

What changed:

• Added generate_content as the issue-specified entry point while keeping the existing generateContent export.
• Added social_card generation, 160-character normalization, return payload support, and outreach_sent storage.
• Added tests for social-card normalization and the generate_content compatibility export.

Validation:

• git diff --check passed.
• Static content-agent acceptance checks passed for the new export, stored payload, returned payload, and test coverage.
• deno test tests/content-agent.test.ts could not run in this local environment because deno is not installed.
• bun test tests/content-agent.test.ts is not a valid substitute here because Bun cannot read the Deno URL import used by the test file.