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/iosApp/project.yml

@@ -0,0 +1,43 @@
+name: iosApp
+options:
+  bundleIdPrefix: dev.uatu.sample
+  deploymentTarget:
+    iOS: "15.0"
+  xcodeVersion: "16.0"
+
+settings:
+  base:
+    ENABLE_USER_SCRIPT_SANDBOXING: NO
+    SWIFT_VERSION: "5.0"
+    ONLY_ACTIVE_ARCH: YES
+    EXCLUDED_ARCHS[sdk=iphonesimulator*]: x86_64
+
+targets:
+  iosApp:
+    type: application
+    platform: iOS
+    sources:
+      - iosApp
+    dependencies:
+      - framework: ../composeApp/build/bin/iosSimulatorArm64/debugFramework/ComposeApp.framework
+        embed: false
+      - sdk: libsqlite3.tbd
+    settings:
+      base:
+        PRODUCT_BUNDLE_IDENTIFIER: dev.uatu.sample
+        PRODUCT_NAME: iosApp
+        INFOPLIST_FILE: iosApp/Info.plist
+        FRAMEWORK_SEARCH_PATHS:
+          - $(SRCROOT)/../composeApp/build/bin/$(KOTLIN_FRAMEWORK_DIR)/debugFramework
+        OTHER_LDFLAGS:
+          - -ObjC
+        KOTLIN_FRAMEWORK_DIR: iosSimulatorArm64
+    preBuildScripts:
+      - name: Build Kotlin framework
+        script: |
+          cd "$SRCROOT/.."
+          ANDROID_HOME="${ANDROID_HOME:-$HOME/Library/Android/sdk}" \
+            ./gradlew :composeApp:linkDebugFrameworkIosSimulatorArm64
+        outputFiles:
+          - $(SRCROOT)/../composeApp/build/bin/iosSimulatorArm64/debugFramework/ComposeApp.framework/ComposeApp
+        basedOnDependencyAnalysis: false