fix(transform): closes #342 — cond ? await a() : b() evaluates BOTH branches

[proggeramlug]

What's broken

A conditional expression with await on one side ran the awaited call regardless of the condition. The original repro from #342:

async function a(): Promise<number> { console.log('ran a'); return 1; }
function       b():        number    { console.log('ran b'); return 2; }
async function main(): Promise<void> {
  const cmd: string = 'digest';
  const r = cmd === 'fetch' ? await a() : b();
  console.log('r=' + r);
  process.exit(0);
}
main().catch((e) => { console.log(e); process.exit(1); });

Buggy output: ran a / ran b / r=2 (a ran even though the digest branch was taken).

Root cause

Not codegen — the async→generator pre-pass. The hoister blindly walks expression children looking for Expr::Await and lifts each into a let __await_N = await X placed BEFORE the containing statement. So

let r = cond ? await a() : b();

becomes

let __await_N = await a();
let r = cond ? __await_N : b();

— a() runs unconditionally. --print-hir confirms it: then_expr: LocalGet(N), and the original Call got moved to state 0 of the generator state machine.

Fix

Detect Expr::Conditional whose then- or else-branch contains an await and, before any general hoisting walks into it, lift the whole conditional to a statement-level if/else with a temp local:

let __cond_await_N: any;
if (cond) { __cond_await_N = await a(); }
else      { __cond_await_N = b(); }
let r = __cond_await_N;

The recursive hoist_awaits_in_stmts call inside each branch then hoists the await to the top of its own if-arm — the position the await→yield rewrite expects. Both hoist_awaits_in_expr_full and hoist_awaits_avoiding_top_level get the early dispatch, so the lift fires whether the conditional is at let-init or in a deeper position.

Verification

All four await-shape combinations behave correctly:

Shape	Before	After
cond ? await a() : b()	both branches	only matched
cond ? a() : await b()	both branches	only matched
cond ? await a() : await b()	both branches	only matched
cond ? a() : b() (sync only)	already correct	unchanged

Plus the actual skelpo-listener pattern that surfaced the bug:

const code = args.command === 'fetch' ? await runFetch(args) : runDigest(args);

now runs only runDigest on a digest invocation.

cargo build --release -p perry clean.

Closes #342