docs: replace stale 'android' name mentions with 'iris'

The plugin is named 'iris' (IrisAdapter, IRIS_HOME_CHANNEL, label Iris),
but several docs still referred to it as the android platform/plugin and
to the product as 'the Android app'. Rename name-mentions to iris/IRIS
and product-mentions to 'Iris app'; keep legitimate OS references
(androidApp, Android SDK, Android 10, androidx, test_android.py, ...).

Also includes pi-lens markdown-lint autofixes (table spacing, trailing
newlines) in the touched files.

docs/10-android-app.md

@@ -1,4 +1,4 @@
-# 10 — Android App (Kotlin + Jetpack Compose)
+# 10 — Iris App (Android; Kotlin + Jetpack Compose)
 
 Native client. Lives in the Compose Multiplatform project at `app/`; the bulk of
 the code is in `app/shared` (commonMain) so the Desktop app reuses it.