StatementFeatureVisitor purity check misses AnalyticExpression (f(x) OVER ..) and TranscodingFunction (CONVERT .. USING) #2575

Statement.getFeatures(pureFunctions) is meant to report every function the caller cannot prove pure, so a read-only guard can refuse it (usage.rst, "Proven, possible, excluded"). Two expression kinds never reach that check, so a guard built on getUnresolvedReferences() / mayModifyData() lets them through.

Version: com.manticore-projects.jsqlformatter:jsqlparser:5.4.351-SNAPSHOT (build 5.4.351-20260910.100601-1), same on master at b2115ac8.

Reproduce

Predicate<String> nothingIsPure = name -> false;

// window-form call: the name pg_sleep is never tested
StatementFeatures f = CCJSqlParserUtil.parse("SELECT pg_sleep(1) OVER () FROM t").getFeatures(nothingIsPure);
f.getUnresolvedReferences();   // []      expected [pg_sleep]
f.mayModifyData();             // false   expected true

// CONVERT .. USING: same
f = CCJSqlParserUtil.parse("SELECT CONVERT(name USING utf8) FROM t").getFeatures(nothingIsPure);
f.getUnresolvedReferences();   // []      expected [convert]

// for comparison, the plain call is reported
f = CCJSqlParserUtil.parse("SELECT pg_sleep(1) FROM t").getFeatures(nothingIsPure);
f.getUnresolvedReferences();   // [pg_sleep]

Cause

StatementFeatureVisitor.FeatureExpressionVisitor overrides visit(Function) (StatementFeatureVisitor.java:836-848) and the table-function case, but not visit(AnalyticExpression) (getName()) and visit(TranscodingFunction). An AnalyticExpression wraps the call itself; its getExpression() is the argument, not a Function, so the inherited traversal never produces a Function node for the name.

Suggestion

Treat AnalyticExpression.getName() like a Function name in the purity check, and TranscodingFunction as a function named convert (or its getTranscodingName()), so mayModifyData() and getUnresolvedReferences() cover f(x) OVER (..) and CONVERT(x USING y). A negative test in StatementFeatureVisitorTest next to unprovenFunctionIsPossibleNotCertain would pin it.