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/20-qr-pairing.md

@@ -315,7 +315,7 @@ interleaved (different languages, no shared surface).
 
 - **QR display in the app** (showing a QR for other devices to scan) —
   single-device pairing today; revisit if multi-device lands.
-- **`hermes android pair` stretch CLI** (re-issue token + new QR,
+- **`hermes iris pair` stretch CLI** (re-issue token + new QR,
   `09-pairing-security.md` §9.2 line 48) — separate backlog item.
 - **WSS cert pinning** (gap #6) — orthogonal; QR carries `secure=1`
   already, pinning is app-side.