Port sample-app to KMP with Android, iOS, Web, and SQLite (#16)

* chore(sample-app): hoist gradle wrapper to sample-app root

* chore(sample-app): add KMP root gradle config

* chore(sample-app): add composeApp KMP module build config

* chore(sample-app): add Android manifest for composeApp

* feat(sample-app): add shared domain models and auth constants

* feat(sample-app): add shared number and date formatting

* feat(sample-app): add cross-platform storage, clock, and id

* feat(sample-app): add shared repository with file-backed state

* feat(sample-app): add shared in-memory navigator

* feat(sample-app): add Compose theme and design tokens

* feat(sample-app): add shared UI components (icons, screen, widgets)

* feat(sample-app): add Login and Home pages

* feat(sample-app): add AddAccount, Ledger, AddTransaction pages

* feat(sample-app): add App root composable with routing

* feat(sample-app): add Android Application and Activity hosting Compose UI

* chore(sample-app): remove legacy android module (replaced by composeApp)

* chore(sample-app): bump to latest stable Kotlin/AGP/Compose deps

* fix(sample-app): make iOS compile (drop @Volatile, set bundleId)

* feat(sample-app): add xcodegen spec, SwiftUI host, and iOS Info.plist

* chore(sample-app): ignore build artifacts and generated xcodeproj

* chore(sample-app): update justfile for composeApp layout, add ios target

* docs(sample-app): rewrite README for KMP + iOS flow

* refactor(sample-app): drop in-app status bar and formatClock

* feat(sample-app): add SQLDelight schema and per-platform drivers

* refactor(sample-app): back Repository with SQLite, drop file serializer

* feat(sample-app): wire native back on Android and iOS edge swipe

* feat(sample-app): semantic roles, labels, and a11y descriptions

* fix(sample-app): link libsqlite3 for iOS target

SQLDelight's native driver needs libsqlite3.tbd on iOS; without it the
linker fails with undefined _sqlite3_bind_blob and friends.

* refactor(sample-app): abstract storage behind LedgerStore interface

Platform-specific createLedgerStore() returns a SqlLedgerStore backed
by SQLDelight on Android + iOS. Opens the door for a pure in-memory
web implementation that does not require a SQLite driver.

* feat(sample-app): add wasmJs target with in-memory LedgerStore

Wires a Compose Multiplatform browser canvas entry point. The web
implementation of LedgerStore is an in-memory model with localStorage
persistence, so it does not need a SQLite driver. Back navigation maps
the browser back button to the same BackHandler contract Android and
iOS use.

* chore(sample-app): settings + gitignore for wasmJs dev run

Registers the Node.js distributions repository and switches
repositoriesMode to PREFER_PROJECT so the Kotlin wasmJs plugin can
download its toolchain. Adds kotlin-js-store (lockfile) and ignores
runs/, web screenshots, playwright-mcp scratch output.

* fix(sample-app): singularize transaction count on Home

Shows "1 transaction" not "1 transactions" for accounts with a single
transaction; falls back to "$count transactions" otherwise.

examples/sample-app/justfile

@@ -6,7 +6,7 @@ avd      := env_var_or_default("AVD", "")
 duration := env_var_or_default("DURATION", "1m")
 seed     := env_var_or_default("SEED", "0")
 output   := env_var_or_default("OUTPUT", justfile_directory() / "runs")
-android  := justfile_directory() / "android"
+ios_device := env_var_or_default("IOS_DEVICE", "iPhone 17 Pro")
 
 default:
     @just --list
@@ -40,21 +40,46 @@ install:
     #!/usr/bin/env bash
     set -euo pipefail
     export ANDROID_HOME="$(just _android-home)"
-    cd {{android}} && ./gradlew installDebug
+    ./gradlew :composeApp:installDebug
 
 # Remove the sample APK from the connected device.
 uninstall:
     #!/usr/bin/env bash
     set -euo pipefail
     export ANDROID_HOME="$(just _android-home)"
-    cd {{android}} && ./gradlew uninstallDebug
+    ./gradlew :composeApp:uninstallDebug
 
-# Remove the gradle build directory.
+# Remove gradle + iOS build directories.
 clean:
     #!/usr/bin/env bash
     set -euo pipefail
     export ANDROID_HOME="$(just _android-home)"
-    cd {{android}} && ./gradlew clean
+    ./gradlew clean
+    rm -rf iosApp/build
+
+# Regenerate iosApp.xcodeproj from project.yml.
+ios-gen:
+    #!/usr/bin/env bash
+    set -euo pipefail
+    cd iosApp && xcodegen generate
+
+# Build + install + launch on a booted iOS simulator (boots IOS_DEVICE if none).
+ios:
+    #!/usr/bin/env bash
+    set -euo pipefail
+    export ANDROID_HOME="$(just _android-home)"
+    if ! xcrun simctl list devices booted | grep -q Booted; then
+      xcrun simctl boot "{{ios_device}}"
+      open -a Simulator
+      sleep 3
+    fi
+    just ios-gen
+    xcodebuild -project iosApp/iosApp.xcodeproj -scheme iosApp \
+      -destination 'platform=iOS Simulator,name={{ios_device}}' \
+      -derivedDataPath iosApp/build \
+      build | tail -5
+    xcrun simctl install booted iosApp/build/Build/Products/Debug-iphonesimulator/iosApp.app
+    xcrun simctl launch booted dev.uatu.sample
 
 # Run 'uatu test' against the sample app. Uses a connected device if one is
 # online, otherwise boots AVD=<name> if provided.