feat!: return full FetchResponse from context.fetch()

[TheRealAgentK]

Summary

Closes #12. context.fetch() now returns a FetchResponse dataclass instead of the raw parsed body, giving callers access to HTTP status codes and response headers.

Changes

Implementation

• Added FetchResponse dataclass with status, headers, and data fields
• Updated ExecutionContext.fetch() to return FetchResponse (return type + body)
• Exported FetchResponse from __init__.py

Docs & samples

• Updated all manual docs (billing.md, building_your_first_integration.md, connected_account.md, integration_structure.md, patterns.md)
• Updated all code samples (api-fetch, template)
• Updated all docstrings in integration.py

Migration plan

• Added docs/plans/12.md with a full audit of all downstream repos that need updating (4 repos, ~100 Python files, 3 markdown files)

Breaking change

Callers must now use response.data to access the parsed body:

# Before
response = await context.fetch(url)
items = response.get("items")

# After
response = await context.fetch(url)
items = response.data.get("items")

See docs/plans/12.md for the full rollout plan across autohive-integrations, integrations, Autohive, and autohive-docs.

[Hamish-taylor]

Just one comment about the plan file. But I am happy with the code

[Hamish-taylor]

Does this plan file belong in this repo? 🤔

[TheRealAgentK]

That's a fair question, but I think it's useful - I'm a big fan of information in the repo and given that - while 12 is completed in here - there's follow-up work I want to audit against at some point when this change goes into a release, I think it's a good place. Happy to remove in the future.

The other options are to put it into a discussion thread, a new GH issue or in our internal Notion, but none of those are ideal either.

[TheRealAgentK]

Please don't merge for the time being - waiting for the Action Error PR (#19) to be merged first.