full sdk 34 support (#4224)

builds upon work from #4082 

Additionally fixes some deprecations and adds support for [predictive
back](https://developer.android.com/guide/navigation/custom-back/predictive-back-gesture).
I also refactored how the activity transitions work because they are
closely related to predictive back. The awkward
`finishWithoutSlideOutAnimation` is gone, activities that have been
started with slide in will now automatically close with slide out.

To test predictive back you need an emulator or device with Sdk 34
(Android 14) and then enable it in the developer settings.

Predictive back requires the back action to be determined before it
actually occurs so the system can play the right predictive animation,
which made a few reorganisations necessary.

closes #4082 
closes #4005 
unlocks a bunch of dependency upgrades that require sdk 34

---------

Co-authored-by: Goooler <wangzongler@gmail.com>

app/src/main/java/com/keylesspalace/tusky/view/ClickableSpanTextView.kt

@@ -373,21 +373,21 @@ class ClickableSpanTextView @JvmOverloads constructor(
         return firstDiff < secondDiff
     }
 
-    override fun onDraw(canvas: Canvas?) {
+    override fun onDraw(canvas: Canvas) {
         super.onDraw(canvas)
 
         // Paint span boundaries. Optimised out on release builds, or debug builds where
         // showSpanBoundaries is false.
         if (BuildConfig.DEBUG && showSpanBoundaries) {
-            canvas?.save()
+            canvas.save()
             for (entry in delegateRects) {
-                canvas?.drawRect(entry.key, paddingDebugPaint)
+                canvas.drawRect(entry.key, paddingDebugPaint)
             }
 
             for (entry in spanRects) {
-                canvas?.drawRect(entry.key, spanDebugPaint)
+                canvas.drawRect(entry.key, spanDebugPaint)
             }
-            canvas?.restore()
+            canvas.restore()
         }
     }