feat: LTL operators, sampling, and default generators (#17)

* feat(ltl): add Now/Next/Eventually/Implies/Or/And/Not formulas

Replace the fold-with-latch evaluator with a residual-formula reducer.
Each Observe() instantiates a fresh obligation from the root (stripping
an outer Always), reduces each pending obligation against current state,
latches Violated on first failure, and surfaces Pending verdicts for
deferred obligations. Existing Always/Pure/Thunk tests continue to pass.

* feat(ltl): support relative duration for eventually().within()

* feat(proto): add Swipe, PressKey, RecentLogs RPCs

* feat(verifier,runner): formula handles, new action kinds, rich state

- verifier: add formula-spec registry; bindNow/bindNext/bindEventually with
  chainable .implies/.or/.and/.not and .within(n,unit) on eventually; bindFrom
  for uniform sampling. bindAlways keeps accepting plain predicates.
- verifier: store lastTree, lastAction, step time, logs, exceptions on the
  Verifier; SnapshotInput replaces the (snapshots, tree) pair. stateObject now
  produces state.lastAction/time/logs/exceptions matching the TS State type.
- verifier: make taps/swipes/waitOnce/pressKey built-in generators actually
  fire; taps picks a clickable, enabled element from the last hierarchy.
- agent: add exceptions field to Message wire format.
- driver: add Swipe/PressKey/RecentLogs to Driver interface; wire maestro
  client and mock driver. LogEntry exposed for runner consumption.
- runner: apply Swipe/PressKey/Wait actions; collect logcat and exceptions;
  pass lastAction and step time into PushSnapshot.

* feat(spec-api): LTL operators, new actions, richer State

- ltl.ts exports now/next/eventually; always overload accepts a Formula
- types.ts: Formula gains implies/or/and/not; EventuallyFormula adds .within;
  State gains lastAction/time/logs/exceptions; Swipe/PressKey/Wait action types
- actions.ts: Swipe/PressKey/Wait/from constructors; waitOnce + pressKey
  default generators
- tests exercise the chaining, sampling, and new actions through a recorded
  fake runtime

* feat(sidecar): add swipe, pressKey, recentLogs RPC handlers

* feat(sdk-android): capture uncaught exceptions

Install a default uncaught handler on Uatu.start, chained with any
existing handler so Android's crash reporter still runs. Expose
Uatu.reportError for callers to forward caught throwables. A bounded
circular buffer (default 50) drains into each STATE message's new
exceptions field. Protocol.kt serializes/deserializes the field,
matching the Go wire format added to internal/agent/protocol.go.

* feat(spec-api): add @uatu/spec/defaults/properties bundle

* feat(sample-app): exercise new LTL operators + defaults

spec.ts now imports eventually/next/now/from from @uatu/spec and
noUncaughtExceptions from @uatu/spec/defaults/properties. It declares
three properties that exercise the new surface:

- accountCountNonNegative: plain always() safety
- addAccountAdvances: always(now(x).implies(next(y)))
- eventuallyLoggedIn: eventually(p).within(30, "seconds")
- noUncaughtExceptions: imported default

The weighted actions root uses from() for random phone/name sampling
and entries for taps/swipes/waitOnce/pressKey built-ins.

SampleApplication gains a debug hook gated on the system property
uatu.inject_error so the e2e run can synthesize an Uatu.reportError and
verify noUncaughtExceptions violates.

cmd/uatu/test_run.go adds a subpath alias so specs importing
"@uatu/spec/defaults/properties" resolve against the in-tree source
when running from the uatu checkout. The spec-integration tests swap
the old click-counter fixtures for the new login hierarchy.

* feat(trace): record swipe/key/wait details + exceptions

trace.Step gains an Exceptions array so the trace captures the
class/message/stackTrace for each SDK-reported throwable in a step.
trace.Action gains FromX/FromY/ToX/ToY/Key/DurationMillis so the full
payload of Swipe/PressKey/Wait actions is visible in trace.jsonl.

sample-app's debug error hook now gates on ApplicationInfo.DEBUGGABLE
instead of a system property (adb setprop fails on non-rooted
emulators).

internal/verifier/verifier_test.go

@@ -60,10 +60,10 @@ func TestPushSnapshot_UpdatesExtractorCurrentAndPrevious(t *testing.T) {
 	verifier := newVerifier(t)
 	mustLoad(t, verifier, helloSpec)
 
-	if err := verifier.PushSnapshot(Snapshots{
+	if err := verifier.PushSnapshot(SnapshotInput{Snapshots: Snapshots{
 		"screen":         json.RawMessage(`"customer_ledger"`),
 		"ledger.balance": json.RawMessage(`1500`),
-	}, nil); err != nil {
+	}}); err != nil {
 		t.Fatal(err)
 	}
 
@@ -78,7 +78,7 @@ func TestPushSnapshot_UpdatesExtractorCurrentAndPrevious(t *testing.T) {
 	}
 
 	// Push again: previous should mirror the prior current.
-	if err := verifier.PushSnapshot(Snapshots{"ledger.balance": json.RawMessage(`2000`)}, nil); err != nil {
+	if err := verifier.PushSnapshot(SnapshotInput{Snapshots: Snapshots{"ledger.balance": json.RawMessage(`2000`)}}); err != nil {
 		t.Fatal(err)
 	}
 	balanceValue = verifier.runtime.GlobalObject().Get("balance").ToObject(verifier.runtime)
@@ -105,7 +105,7 @@ func TestEvaluateProperties_HoldsThenViolates(t *testing.T) {
 	}
 	for index, testCase := range cases {
 		raw, _ := json.Marshal(testCase.balance)
-		if err := verifier.PushSnapshot(Snapshots{"ledger.balance": raw}, nil); err != nil {
+		if err := verifier.PushSnapshot(SnapshotInput{Snapshots: Snapshots{"ledger.balance": raw}}); err != nil {
 			t.Fatal(err)
 		}
 		verdicts := verifier.EvaluateProperties()
@@ -118,7 +118,7 @@ func TestEvaluateProperties_HoldsThenViolates(t *testing.T) {
 func TestNextAction_FromActionsGenerator(t *testing.T) {
 	verifier := newVerifier(t)
 	mustLoad(t, verifier, helloSpec)
-	_ = verifier.PushSnapshot(Snapshots{}, nil)
+	_ = verifier.PushSnapshot(SnapshotInput{Snapshots: Snapshots{}})
 
 	action, err := verifier.NextAction()
 	if err != nil {
@@ -142,7 +142,7 @@ func TestNextAction_WeightedSelectsByWeight(t *testing.T) {
 			[99, tapAway],
 		);
 	`)
-	_ = verifier.PushSnapshot(Snapshots{}, nil)
+	_ = verifier.PushSnapshot(SnapshotInput{Snapshots: Snapshots{}})
 
 	awayCount := 0
 	homeCount := 0
@@ -168,7 +168,7 @@ func TestNextAction_EmptyGeneratorReturnsErrNoAction(t *testing.T) {
 	mustLoad(t, verifier, `
 		globalThis.actions = __uatu__.actions(() => []);
 	`)
-	_ = verifier.PushSnapshot(Snapshots{}, nil)
+	_ = verifier.PushSnapshot(SnapshotInput{Snapshots: Snapshots{}})
 
 	_, err := verifier.NextAction()
 	if !errors.Is(err, ErrNoAction) {
@@ -183,7 +183,7 @@ func TestInputText_RoundTrip(t *testing.T) {
 			__uatu__.inputText({ into: "id:phone", text: "+919876543210" }),
 		]);
 	`)
-	_ = verifier.PushSnapshot(Snapshots{}, nil)
+	_ = verifier.PushSnapshot(SnapshotInput{Snapshots: Snapshots{}})
 
 	action, err := verifier.NextAction()
 	if err != nil {
@@ -202,7 +202,7 @@ func TestPushSnapshot_FeedsSnapshotsToExtractorState(t *testing.T) {
 	mustLoad(t, verifier, `
 		globalThis.captured = __uatu__.extract(state => state.snapshots["k"]);
 	`)
-	if err := verifier.PushSnapshot(Snapshots{"k": json.RawMessage(`"hello"`)}, nil); err != nil {
+	if err := verifier.PushSnapshot(SnapshotInput{Snapshots: Snapshots{"k": json.RawMessage(`"hello"`)}}); err != nil {
 		t.Fatal(err)
 	}
 	value := verifier.runtime.GlobalObject().Get("captured").ToObject(verifier.runtime).Get("current")