tests: add lazy-state integration tests

[AchrafReyani]

Short Description

Adds 21 lazy-state ($) tests to integration-tests/execute/test/lazy-state.test.ts, building up from simple reads to expressions, mapping/iteration, scoping rules and illegal usage.

Fixes #840

Implementation Details

The new tests are grouped and ordered methodically, following the examples on the Lazy State Operator docs page:

• Basic reads – top-level value, nested path, array index, optional chaining on a missing path, and fn($.data) returning a value from state as the next state.
• Expressions – arithmetic, && / || / !, ternary, and $ as a dynamic property key (codes[$.location.country]).
• Objects, mapping and iteration – mapping state into an object argument (the docs' create('agent', { name: $.patient.name }) shape, via a tiny in-job upsert helper that resolves its argument the way expandReferences does), each($.data.items, …), reading the current item with $.data inside each(), and group($.data.rows, $.keyPath).
• Scoping – $ declared as a parameter or a local const is left alone; $ inside a string literal is not converted.
• Illegal usage – every ❌ example from the docs asserts the LazyStateError message: assigning $ to a variable, using it inside a nullary arrow, inside an arrow whose parameter isn't named state, and writing to $ at the top level or inside an operation.

No source changes; only the test file is touched. No changeset added since @openfn/integration-tests-execute is private (same as previous test-only changes here).

One thing I noticed while writing these and deliberately left out: a method call on a nested state value, e.g. fnIf($.name.toUpperCase() === 'JOHN', …), currently compiles to (state => state.name.toUpperCase)() === 'JOHN' – the arrow wraps the callee rather than the call (the special case in ensureParentArrow only handles $.method() directly on state). Happy to open a separate issue for that if useful.

QA Notes

Ran in a clean node:22 Linux container (fresh pnpm install --frozen-lockfile + pnpm -r --filter=./packages/* run build):

integration-tests/execute $ pnpm ava test/lazy-state.test.ts --verbose
  ✔ … (23 tests)
  23 tests passed

integration-tests/execute $ pnpm ava
  35 tests passed
  1 test skipped

Also tsc --noEmit -p integration-tests/execute/tsconfig.json and prettier --check on the file pass.

(Side note, not addressed here: on Windows the whole execute integration suite fails before any test runs because the runtime linker builds file://C:\… instead of a file:///C:/… URL; CI on Linux is unaffected.)

AI Usage

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