Remove in-app SDK (#43)

* chore: delete internal/agent package

* chore(build): remove sdk-android from gradle settings

* chore(makefile): remove sdk-android targets

* chore(ci): remove release-android job from release workflow

* chore(folio): remove sdk-android dependency

* chore(folio): remove SDK initialization from FolioApplication

* chore(folio): delete snapshot extractor files

* feat(folio): add balance to account card content description

* feat(folio): add hierarchy content descriptions to LedgerScreen

* refactor(folio): rewrite spec.ts to use ax extractors

* docs: remove in-app SDK from README

* feat(folio): add focused_input indicator to App

* docs: remove in-app SDK from index

* refactor(runner): remove agent SDK connection and snapshot step

* test(runner): update tests for SDK removal

* docs: remove Android SDK section from getting-started

* refactor(testrun): remove agent SDK connection setup

* docs: remove snapshots from writing-specs

* docs: remove in-app SDK from architecture doc

* docs(folio): update README for SDK removal

* docs: update per-step cycle diagram in architecture doc

* fix(folio): detect screens from unique element presence, not id: selectors

testTag() in Compose is not exposed as resource-id without testTagsAsResourceId.
Use desc: selectors for elements unique to each screen instead of id: path queries.

* feat(folio): add screen root contentDescription for scoped ax selection

Each screen root gets semantics { contentDescription = "ScreenName" } so
sanderling specs can scope element lookups through the screen: desc:LoginScreen > desc:login_submit.

* fix(folio): scope all ax selectors through screen root nodes

Use desc:ScreenName > desc:element path queries so every selector is
rooted at the screen level. focusedInput stays unscoped since it lives
in the app root, outside any screen.

* fix(folio): guard newAccountBalanceIsZero against navigation false positives

Scoped selectors return [] when not on HomeScreen so accounts vanish and
reappear as apparently-new on each visit. Skip the check when prev was empty.

* chore(folio): link @sanderling/spec to local pkg/spec for IDE type checking

* feat(spec): add desc, class, clickable, enabled, checked, focused, selected to AccessibilityElement

Runtime fields set by the verifier were missing from the TypeScript type,
causing linting errors on el.desc and related accesses in specs.

* chore(folio): switch to bun, add tsconfig.json for IDE type checking

- Remove package-lock.json, add bun.lock
- Add tsconfig.json so VSCode resolves @sanderling/spec types
- Fix parseAccount/parseLedgerRow to accept string | undefined

examples/folio/sanderling/spec.ts

@@ -12,7 +12,6 @@ import {
 
 interface Account {
   id: string;
-  name: string;
   balance: number;
 }
 
@@ -21,31 +20,70 @@ interface LedgerRow {
   signed: number;
 }
 
-const loggedIn = extract<boolean>(s => (s.snapshots.logged_in as boolean) ?? false);
-const route = extract<string>(s => (s.snapshots.screen as string) ?? "");
-const accounts = extract<Account[]>(s => (s.snapshots.accounts as Account[]) ?? []);
-const ledgerRows = extract<LedgerRow[]>(s => (s.snapshots.ledger_rows as LedgerRow[]) ?? []);
-const ledgerBalance = extract<number>(s => (s.snapshots.ledger_balance as number) ?? 0);
-const activeAccountId = extract<string | null>(s => (s.snapshots.active_account_id as string | null) ?? null);
-const focusedInput = extract<string | null>(s => (s.snapshots.focused_input as string | null) ?? null);
+function parseAccount(desc: string | undefined): Account {
+  const parts = (desc ?? "").split(":");
+  return { id: parts[1] ?? "", balance: Number(parts[2]) };
+}
 
-const loginEmailField = extract(s => s.ax.find("id:LoginScreen > desc:login_email"));
-const loginPasswordField = extract(s => s.ax.find("id:LoginScreen > desc:login_password"));
-const loginSubmit = extract(s => s.ax.find("id:LoginScreen > desc:login_submit"));
-const addAccountButton = extract(s => s.ax.find("id:HomeScreen > desc:add_account_button"));
-const accountNameField = extract(s => s.ax.find("id:AddAccountScreen > desc:account_name_field"));
-const addAccountSubmit = extract(s => s.ax.find("id:AddAccountScreen > desc:add_account_submit"));
-const addTxnButton = extract(s => s.ax.find("id:LedgerScreen > desc:add_txn_button"));
-const txnAmountField = extract(s => s.ax.find("id:AddTransactionScreen > desc:txn_amount"));
-const txnSubmit = extract(s => s.ax.find("id:AddTransactionScreen > desc:txn_submit"));
-const accountCards = extract(s => s.ax.findAll("descPrefix:account_card:"));
+function parseLedgerRow(desc: string | undefined): LedgerRow {
+  const parts = (desc ?? "").split(":");
+  return { id: parts[1] ?? "", signed: Number(parts[2]) };
+}
+
+function parseCents(desc: string | null | undefined): number {
+  if (!desc) return 0;
+  const parts = desc.split(":");
+  return Number(parts[1]) || 0;
+}
+
+// Route and auth state derived from screen root nodes
+const loggedIn = extract(s => s.ax.find("desc:LoginScreen") == null);
+const route = extract<string | null>(s => {
+  if (s.ax.find("desc:LoginScreen")) return "login";
+  if (s.ax.find("desc:HomeScreen")) return "home";
+  if (s.ax.find("desc:AddAccountScreen")) return "add-account";
+  if (s.ax.find("desc:LedgerScreen")) return "ledger";
+  if (s.ax.find("desc:AddTransactionScreen")) return "add-transaction";
+  return null;
+});
+
+// All element lookups scoped through their screen root
+const accounts = extract(s => s.ax.findAll("desc:HomeScreen > descPrefix:account:")
+  .map(el => parseAccount(el.desc)));
+const ledgerRows = extract(s => s.ax.findAll("desc:LedgerScreen > descPrefix:ledger_row:")
+  .map(el => parseLedgerRow(el.desc)));
+const ledgerBalance = extract(s =>
+  parseCents(s.ax.find("desc:LedgerScreen > descPrefix:ledger_balance:")?.desc));
+const activeAccountId = extract(s =>
+  s.ax.find("desc:LedgerScreen > descPrefix:active_account:")?.desc?.split(":")[1] ?? null);
+
+// focusedInput lives in the app root (not inside any screen), so unscoped
+const focusedInput = extract(s =>
+  s.ax.find("descPrefix:focused_input:")?.desc?.split(":")[1] ?? null);
+
+const loginEmailField = extract(s => s.ax.find("desc:LoginScreen > desc:login_email"));
+const loginPasswordField = extract(s => s.ax.find("desc:LoginScreen > desc:login_password"));
+const loginSubmit = extract(s => s.ax.find("desc:LoginScreen > desc:login_submit"));
+const addAccountButton = extract(s => s.ax.find("desc:HomeScreen > desc:add_account_button"));
+const accountNameField = extract(s => s.ax.find("desc:AddAccountScreen > desc:account_name_field"));
+const addAccountSubmit = extract(s => s.ax.find("desc:AddAccountScreen > desc:add_account_submit"));
+const addTxnButton = extract(s => s.ax.find("desc:LedgerScreen > desc:add_txn_button"));
+const txnAmountField = extract(s => s.ax.find("desc:AddTransactionScreen > desc:txn_amount"));
+const txnSubmit = extract(s => s.ax.find("desc:AddTransactionScreen > desc:txn_submit"));
+const accountCards = extract(s => s.ax.findAll("desc:HomeScreen > descPrefix:account:"));
 const backButton = extract(s => s.ax.find("desc:Back"));
 
 // Property 1: every new account starts with balance === 0
+// Guard: only check when accounts were visible in the previous step too.
+// Without this, navigating away from HomeScreen (accounts=[]) then back
+// makes every account look "new", causing false positives on pre-existing balances.
 const newAccountBalanceIsZero = always(
   next(() => {
-    const prevIds = new Set((accounts.previous ?? []).map(a => a.id));
-    const newAccounts = accounts.current.filter(a => !prevIds.has(a.id));
+    const prev = accounts.previous ?? [];
+    const curr = accounts.current;
+    if (prev.length === 0 || curr.length === 0) return true;
+    const prevIds = new Set(prev.map(a => a.id));
+    const newAccounts = curr.filter(a => !prevIds.has(a.id));
     return newAccounts.every(a => a.balance === 0);
   })
 );
@@ -69,7 +107,7 @@ const newTxnChangesBalance = always(
 const DEMO_EMAIL = "[email protected]";
 const DEMO_PASSWORD = "ledger123";
 
-// Login if not already in — step by step based on which field has focus
+// Login if not already in - step by step based on which field has focus
 const login = actions(() => {
   if (loggedIn.current) return [];
   const focus = focusedInput.current;