Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@tests/test_checker.py`:
- Around line 3308-3335: Add a test that locks the argument order for piping
into module-qualified calls that already take arguments: create a new test (e.g.
test_pipe_module_call_arg_order_regression) that uses the same mod =
self._resolved(("math",), self.MATH_MODULE) setup and constructs a source where
a value is piped into a module call that already has an asymmetric argument (for
example: `{ `@Int.0` |> math::max(123) }`) then run parse_to_ast and typecheck
with resolved_modules=[mod] and assert no error diagnostics; this ensures the
pipe inserts the receiver as the first argument (math::max(value, 123)) rather
than appending and will catch future prepend/append regressions.

Verify each finding against the current code and only fix it if needed.

Outside diff comments:
In `@TESTING.md`:
- Around line 83-120: Update TESTING.md so all conformance counts match the
conformance suite's actual size (65 programs). Replace the outdated numeric
references ("315 tests" and every "64 conformance programs") with the correct
values consistent with the manifest and the section that lists 65 programs;
double-check the Directory structure and any "Count" column entries in the "Test
levels" table and the textual summaries to use 65 where appropriate (refer to
tests/conformance/ and manifest.json to verify). Ensure no other scattered
references to 64 or 315 remain so the document is internally consistent.

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@tests/test_checker.py`:
- Around line 3322-3334: In test_pipe_chained_module_calls_typechecks, the
source string imports an unused symbol `max`; update the import to only bring in
`abs` by changing the import clause in the test's source from "import math(abs,
max);" to "import math(abs);" so the test only imports what it uses (reference:
the test function name test_pipe_chained_module_calls_typechecks and the source
variable containing the import).
- Around line 3336-3358: The test test_pipe_module_call_arg_order_regression
currently uses math::max which is symmetric (max(`@Int`,`@Int`)) so it cannot catch
prepend-vs-append regressions; change the test to call an asymmetric function
(e.g. math::tag with signature tag(`@Int`,`@String` -> `@String`)) so the LHS being
appended would produce a type error—update the test source to import math(tag)
and use the pipe expression `@Int.0` |> math::tag("ok") (or add tag to MATH_MODULE
and then use that symbol) so the argument ordering is actually validated by the
typechecker.