Implement io.net AI adapter

[op-simoneromeo]

Summary

• replace the ai-ionet stub with a real IO Intelligence OpenAI-compatible chat-completions adapter
• use IOINTELLIGENCE_API_KEY, documented io.net base URL, default/example models, dry-run short-circuiting, extra parameter passthrough, usage mapping, and provider error excerpts
• add focused mocked fetch coverage for dry-run, request shape, response mapping, text-choice fallback, and error handling

Validation

• corepack pnpm@9.12.0 exec vitest run packages/ai/ionet/src/index.test.ts
• corepack pnpm@9.12.0 --filter @profullstack/sh1pt-ai-ionet typecheck
• corepack pnpm@9.12.0 --filter @profullstack/sh1pt-ai-ionet build
• git diff --check
• common secret-pattern scan over the changed io.net files

No real io.net API key or production secret was used; tests mock fetch.

[github-actions]

🤖 Auto-rebase: The branch was rebased successfully locally but could not be pushed to the fork. Please enable 'Allow edits from maintainers' in the PR settings, or rebase manually: git fetch upstream master && git rebase upstream/master.

[github-actions]

🤖 Auto-rebase: The branch was rebased successfully locally but could not be pushed to the fork. Please enable 'Allow edits from maintainers' in the PR settings, or rebase manually: git fetch upstream master && git rebase upstream/master.

[github-actions]

🤖 Auto-rebase: The branch was rebased successfully locally but could not be pushed to the fork. Please enable 'Allow edits from maintainers' in the PR settings, or rebase manually: git fetch upstream master && git rebase upstream/master.