follow-ups from the pr #73 review (#77)

* ci(folio): run gradle on jdk 21 for the metro plugin

the metro gradle plugin folio builds with publishes org.gradle.jvm.version 21
and java 21 class files, so every leg failed at the folio build on a 17
runtime. local builds pass on jdk 25, which is why only ci saw it.

* fix(build): clean pkg/spec/dist, not the dead spec-api path

* chore: point stale spec-api comments at pkg/spec

* fix(spec): publish src so an installed package carries the runtime entries

* fix(testrun): alias the installed spec package so one module graph loads

* fix(spec): export Direction, ScrollAction and LongPressAction from the entry

* docs(spec): cut the package readme to a description and doc links

* docs: say how the cli and spec package versions relate

* fix(verifier): report whether the last action was confirmed applied

Both hosts get applied: true when the runner saw the dispatch succeed and
applied: null when it could not, so an unconfirmed action stops arriving at
the spec as no action at all.

* fix(runner): an apply error leaves the action's fate unknown, not undone

A deadline that fires after the tap was dispatched leaves the effect
committed. Reporting nil made the spec see an effect with no action to cause
it, which is how the counting property convicts a healthy app.

* fix(release): stage the sidecar jar at the renamed embed path

* test(replay-ui): trace fixtures for the vacuity counts

one real green run, one run that rendered nothing, one that judges every property at least once.

* ci(replay-ui): count the steps each property judged

the exit code says no property returned false; it does not say any property was ever evaluated. this reads the trace and reports judged vs declined per property, and fails when the step page never rendered.

* test(replay-ui): cover the summary script from make test

* ci(replay-ui): summarise through the vacuity script

* docs(ci): explain the replay-ui judged/declined counts

* fix(verifier): encode element-valued extractors into the trace

An ax element exports with its find/findAll host functions attached, and
json.Marshal refuses the whole value over them: json: unsupported type:
func(goja.FunctionCall) goja.Value. The encoding failed, curr stayed nil,
and the goja hosts (ios, android) recorded null for every element-valued
extractor in both the per-step diff and the violation witness.

Apply the web host's sanitize rule before marshaling, so one rule encodes
an element on both hosts.

* test(verifier): pin element encoding to one rule on both hosts

* test(runner): assert an element reaches trace.jsonl and its witness

* feat(spec): give state.lastAction an applied field

Three states, not two: no action is a null lastAction, applied: true is an
action the runner confirmed, applied: null is one it dispatched and never
learned the fate of.

* fix(folio): do not attribute an effect to an unconfirmed action

submitChangesBalanceByTypedAmount and createdAccountHasNonZeroBalance both
convict by pinning an effect on the last action, so both decline unless the
runner saw it applied. The fixtures now say which fate they mean.

* test(folio): an unconfirmed submit belongs in the window

The count is an upper bound on the submits a window holds, so the tap that may
have landed counts and committedTransactionsExceedSubmits has nothing to
convict on.

* test(runner): a tap that lands under a failed apply is not a double submit

Drives the real folio counting predicates through the runner against a device
that commits the tap and then times out. The double-submit case is the control:
without it a green proves only that the property never fired.

* test(verifier): pin the three lastAction states on both hosts

The web page is handed the same applied field the goja object exposes, so a
property cannot read one thing on native and another on web.

* docs(spec-language): document the three lastAction states

examples/folio/sanderling/predicates.ts

@@ -123,10 +123,22 @@ export function readHomeCards<T>(args: {
   return { value: reading, carrier: reading, fresh: true };
 }
 
-function isTapOn(
-  lastAction: { kind?: string; on?: string | object } | null,
-  target: string,
-): boolean {
+// state.lastAction as the two hosts build it (internal/verifier/marshal.go
+// lastActionFields), read defensively: every field is what a Go struct decided
+// to emit, not something this file can trust a compile-time shape for.
+//
+// `applied` is true when the runner saw the action's dispatch succeed and null
+// when the apply call failed with the gesture possibly already delivered: an
+// RPC deadline can fire after the tap landed, and nothing can find out
+// afterwards. That is unknown, not "it did not happen", which is what
+// `lastAction === null` says.
+export interface ObservedAction {
+  kind?: string;
+  on?: string | object;
+  applied?: true | null;
+}
+
+function isTapOn(lastAction: ObservedAction | null, target: string): boolean {
   if (lastAction == null) return false;
   if (lastAction.kind !== "Tap" && lastAction.kind !== "DoubleTap") return false;
   const on = lastAction.on;
@@ -138,19 +150,27 @@ function isTapOn(
 // Repository.createTransaction: AddTransactionViewModel.submit() is the only
 // caller, AddTransactionEvent.Submit is the only thing that runs it, and the
 // TxnSubmit button's onClick is the only thing that sends that event.
-export function isTxnSubmitTap(
-  lastAction: { kind?: string; on?: string | object } | null,
-): boolean {
+export function isTxnSubmitTap(lastAction: ObservedAction | null): boolean {
   return isTapOn(lastAction, "TxnSubmit");
 }
 
 // Likewise the only action that creates an account.
-export function isAddAccountSubmitTap(
-  lastAction: { kind?: string; on?: string | object } | null,
-): boolean {
+export function isAddAccountSubmitTap(lastAction: ObservedAction | null): boolean {
   return isTapOn(lastAction, "AddAccountSubmit");
 }
 
+// Did the runner see this action's dispatch succeed? `applied` is null when the
+// apply call failed with the gesture possibly already delivered (an RPC
+// deadline can fire after the tap landed), and the runner has no way to find
+// out afterwards. Such an action may have caused anything the next reading
+// shows, so it counts toward how many submits a window COULD hold, but it never
+// licenses attributing an effect to it: a property that demands the effect of
+// an action that may never have run convicts the app of the runner's own
+// uncertainty.
+export function confirmedApplied(lastAction: ObservedAction | null): boolean {
+  return lastAction != null && lastAction.applied === true;
+}
+
 // Counts the submit actions inside the window the balance property compares
 // over: from the last Home total we read to this step, inclusive of this step's
 // action.
@@ -164,9 +184,15 @@ export function isAddAccountSubmitTap(
 //
 // The reset lands on `fresh`, the same event that advances the carrier, so the
 // count always describes exactly the interval the two compared totals span.
+//
+// A submit whose dispatch the runner could not confirm counts here, because
+// this number is an upper bound on the submits the window holds and the tap may
+// well have landed. Leaving it out is what convicted a healthy app:
+// committedTransactionsExceedSubmits saw a transaction rise of one against a
+// window of zero and called it a double submit.
 export function countSubmitsInWindow(args: {
   previousCount: number;
-  lastAction: { kind?: string; on?: string | object } | null;
+  lastAction: ObservedAction | null;
   fresh: boolean;
 }): { reported: number; next: number } {
   const { previousCount, lastAction, fresh } = args;
@@ -343,7 +369,7 @@ export function homeTxnCountsOf(cards: readonly CardReading[]): Record<string, T
 // same as fine, and both come back false here.
 export function createdAccountHasNonZeroBalance(args: {
   route: string | null;
-  lastAction: { kind?: string; on?: string | object } | null;
+  lastAction: ObservedAction | null;
   typedName: string | undefined;
   before: Account[] | null;
   after: Account[] | null;
@@ -351,6 +377,10 @@ export function createdAccountHasNonZeroBalance(args: {
   const { route, lastAction, before, after } = args;
   if (route !== "home") return false;
   if (!isAddAccountSubmitTap(lastAction)) return false;
+  // A creation nobody can confirm happened is not a creation to attribute a
+  // card to: the card that turned up may be an older account of the same name
+  // scrolling into view.
+  if (!confirmedApplied(lastAction)) return false;
   if (before === null || after === null) return false;
   const typed = (args.typedName ?? "").trim();
   if (typed === "") return false;
@@ -465,7 +495,7 @@ export function parseTypedAmount(text: string | undefined | null): number {
 // the bug: the double-tap is a single action.
 export function submitChangesBalanceByTypedAmount(args: {
   route: string | null;
-  lastAction: { kind?: string; on?: string | object } | null;
+  lastAction: ObservedAction | null;
   submitsInWindow: number;
   typedAmount: number;
   prevTotalBalance: number | null;
@@ -476,6 +506,10 @@ export function submitChangesBalanceByTypedAmount(args: {
 
   if (route !== "home") return true;
   if (!isTxnSubmitTap(lastAction)) return true;
+  // The whole rule is that the delta belongs to THIS submit. A submit the
+  // runner could not confirm may have committed nothing, and a balance that
+  // did not move is then exactly what a healthy app looks like.
+  if (!confirmedApplied(lastAction)) return true;
   if (submitsInWindow !== 1) return true;
   if (typedAmount === 0) return true;
   // An unknown total on either side is not evidence of anything. Comparing one