Language bindings, KDE thumbnails, yapf compare, in-memory encoding

- yapf_encode() / yapf_free_buffer(): encode to memory; yapf_save uses it
- yapf.c also compiles as C++
- `yapf compare`: size and decode speed of the original format vs YAPF,
  with a lossless check
- bindings with tested examples: C++ (header-only), C# (P/Invoke),
  Rust (crate, builds the C code), Go (cgo), Java (FFM API, Java 22+),
  Zig (@cImport), LuaJIT (FFI), TypeScript types for the JS port;
  Python now encodes in memory
- docs/LANGUAGES.md and examples/ with measured results
- KDE Dolphin thumbnail plugin (KF6, CMake)
- README: honest status for Photoshop / VS Code / Figma (not run in the
  apps yet) and macOS (cross-compiled only), platform table

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

bindings/rust/build.rs

@@ -0,0 +1,12 @@
+// Compiles the C library that lives two folders up.
+fn main() {
+    let root = std::path::Path::new(env!("CARGO_MANIFEST_DIR")).join("../..");
+    cc::Build::new()
+        .file(root.join("yapf.c"))
+        .include(&root)
+        .flag_if_supported("-std=c99")
+        .opt_level(2)
+        .compile("yapf");
+    println!("cargo:rerun-if-changed={}", root.join("yapf.c").display());
+    println!("cargo:rerun-if-changed={}", root.join("yapf.h").display());
+}