rename: libcosmic → libcosmic-yoda (fork 0.1.0-yoda)

Fork point: pop-os/libcosmic 1.0.0 + perf/quickwins-bundle + macOS
window controls feature. From here the crate diverges under the yoda
lineage with its own versioning.

Changes:
- Cargo.toml: name = libcosmic-yoda, version = 0.1.0-yoda
- [lib] name = cosmic kept unchanged — consumer code still does 'use cosmic::...'
- examples/*/Cargo.toml: updated all libcosmic dep references to libcosmic-yoda
- i18n/*/libcosmic.ftl renamed to libcosmic_yoda.ftl (71 locales) to match
  the new name expected by fluent_language_loader!() macro

cargo check --lib passes. Examples not yet validated — Phase 2 (Wayland-only
cut) will rework them anyway.

examples/image-button/Cargo.toml

@@ -7,6 +7,6 @@ edition = "2021"
 tracing = "0.1.44"
 tracing-subscriber = "0.3.22"
 
-[dependencies.libcosmic]
+[dependencies.libcosmic-yoda]
 path = "../../"
 features = ["debug", "winit", "wgpu", "tokio"]