Function eval_condition 

pub fn eval_condition(expr: &str, state: &Value) -> bool

Evaluate a Condition-node branch expression against committed workflow state.

Pure + total: never panics; a malformed or unsupported expression returns false.

Truthiness rule (bare-path form)

Falsy: absent path, null, false, 0/0.0, "", [], {}. Everything else is truthy.

Literal parsing (comparison form)

The RHS must be a valid JSON literal: a double-quoted string ("x"), true, false, null, or a JSON number. Bare words (e.g. done) are NOT valid literals; an unparseable RHS causes the whole comparison to return false (fail-closed). Comparison uses typed serde_json::Value equality: "5" != 5.