fix(mofa-foundation): replace 3.14 with 1.5 in WorkflowValue float test

[rahulkr182]

Summary

Fixes #1268

The literal 3.14f64 in test_workflow_value_conversions approximates π and triggers the deny-level clippy::approx_constant lint, causing both cargo test -p mofa-foundation and cargo clippy --all-targets to fail with a hard compiler error.

Changes

Replace 3.14f64 / 3.14 with 1.5f64 / 1.5 — a clean, non-special float that exercises the same WorkflowValue::Float round-trip behaviour without triggering the lint.

- let v: WorkflowValue = 3.14f64.into();
- assert_eq!(v.as_f64(), Some(3.14));
+ let v: WorkflowValue = 1.5f64.into();
+ assert_eq!(v.as_f64(), Some(1.5));

Verification

cargo clippy -p mofa-foundation --tests   # exit 0, no approx_constant errors
cargo test -p mofa-foundation             # all tests pass