The layout pass read its per-page option with `_opt("layout", True)`. The
accessor is `_page_override`. A pod answered

    500 {"detail": "surya ocr failed: name '_opt' is not defined"}

after the image was built, pushed, signed and booted, because nothing executes
these modules until a page reaches a pod: `codai/ocr/workers/*` run OUTSIDE the
package -- the surya worker in its own venv, forbidden from importing codai --
so no test had ever run a line of them. The test I wrote for the layout pass
asserted the SOURCE STRING of that call and proved only that the text was
there.

So the fix comes with a guard that would have caught it: every `_`-prefixed
name a worker module loads must be bound somewhere in that module. Those are
the module's own helpers, so an unbound one is a typo and not a global from
elsewhere. Pure ast + builtins -- no linter, nothing added to requirements --
and it is checked against the bug itself, because a checker that passes
everything is worse than none.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01S8LAP3ueNzQJtwzhgVbq66