vc=84 — rename launcher to 'Straw' + move stream picker into Rust

Two changes:

1. Launcher name is now just 'Straw', not 'Straw debug' — past the
   debug-branding phase. Kept the .debug applicationId suffix (package
   stays com.sulkta.straw.debug) on purpose so fdroid updates install in
   place and the in-app auto-updater keeps working; dropping the suffix
   would change the package id and force a reinstall that wipes everyone's
   subs/history. That's a separate, deliberate release-track cutover.

2. Stream-selection logic moved out of Kotlin (resolveStreamPlayback) into
   the Rust strawcore wrapper as resolve_playback(StreamInfo, max_height)
   -> ResolvedStreams. The app keeps a thin shim that supplies the
   resolution cap (Settings.maxResolution) and attaches SponsorBlock
   segments. Byte-for-byte behavior parity with the old Kotlin picker:
   highest-bitrate stream at/under the cap, lowest-height fallback when
   nothing fits, first-element-wins on ties (matching Kotlin
   maxByOrNull/minByOrNull, not Rust's last-on-ties max_by_key), and
   isNotBlank() handling for the DASH/HLS URLs. First step of moving all
   backend logic to Rust; the picking lives at the FFI boundary because it
   depends on an app setting, keeping strawcore-core a pure extractor.

Wrapper cargo check + clippy clean (no new warnings); FFI surface adds
ResolvedStreams + resolvePlayback, bindings regen at build.

rust/strawcore/src/lib.rs

@@ -21,7 +21,7 @@ mod stream;
 pub use channel::ChannelInfo;
 pub use error::StrawcoreError;
 pub use search::{Page, SearchItem};
-pub use stream::{AudioStreamItem, StreamInfo, VideoStreamItem};
+pub use stream::{AudioStreamItem, ResolvedStreams, StreamInfo, VideoStreamItem};
 
 /// Initialize Android logging + the strawcore-core HTTP downloader.
 /// Kotlin calls this from StrawApp.onCreate(). Idempotent.