vc=28: edge-to-edge player, nav-bar inset, video-track reset, app icon

Three layout/playback fixes on vc=26-27 feedback plus the long-deferred
app icon.

Layout — VideoDetailScreen
  Player surface now fills the screen width (no 16dp side gutters).
  Outer Column dropped its 16dp padding; the player Box hangs off the
  full width with no rounded corners — NewPipe/YouTube look. Everything
  below (title, chips, button row, description, related list) goes back
  into an inner Column with 16dp horizontal + 12dp vertical padding so
  the body still reads correctly.
  Bottom inset: Spacer(windowInsetsBottomHeight(WindowInsets.navigationBars))
  appended at the end of the scrollable column. Last related video can
  scroll up past the gesture pill / 3-button nav instead of being
  obscured by it. (Plain navigationBarsPadding would have pushed the
  whole surface up and left a dead band.)

Black-video fix
  vc=27's Background button disabled the video track on the controller
  via setTrackTypeDisabled(C.TRACK_TYPE_VIDEO, true) and that override
  is sticky. Returning to a video left it audio-only with a black
  surface. Added a LaunchedEffect(controller, streamUrl) that resets
  TrackSelectionParameters to defaults on every entry into detail — if
  the user opened a video page, they want video. The audio-only
  fullscreen toggle and the Background button still set the override
  for the duration of that session; they just no longer leak.

App icon
  Replaced the Android default placeholder (sym_def_app_icon, which
  fdroid was failing to render anyway) with a proper adaptive icon:
    Background: #166534 deep green (sulkta.com brand)
    Foreground: tilted lime parallelogram + white play triangle
      (literal "straw" nod + video-app affordance)
  Adaptive XML in mipmap-anydpi-v26/. PNG fallbacks rendered via
  rsvg-convert at all five mipmap densities (mdpi/hdpi/xhdpi/xxhdpi/
  xxxhdpi) for pre-API-26 devices. Manifest now points at
  @mipmap/ic_launcher and @mipmap/ic_launcher_round.

strawApp/src/main/res/drawable/ic_launcher_background.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="rectangle">
+    <solid android:color="#166534" />
+</shape>

strawApp/src/main/res/drawable/ic_launcher_foreground.xml

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  Adaptive icon foreground for Straw. Canvas is 108x108dp; the visible
+  mask-safe area is roughly the central 66x66dp (centered at 54,54).
+  Two shapes:
+    - a tilted "straw" rectangle (lime, 4ADE80) running diagonally,
+      a literal nod to the app name
+    - a clean white play triangle sitting on top, anchoring the meaning
+      as a video player
+  Foreground sits on the deep-green (#166534) ic_launcher_background.
+-->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <!-- Tilted straw shape — parallelogram, lime green, slight rotation. -->
+    <path
+        android:fillColor="#4ADE80"
+        android:pathData="M 62,18 L 76,22 L 50,90 L 36,86 Z" />
+    <!-- White play triangle, centered. -->
+    <path
+        android:fillColor="#FFFFFF"
+        android:pathData="M 44,40 L 78,57 L 44,74 Z" />
+</vector>