studio: version text in the status bar, favicon

The status bar ends with "isokit <engine version>"; the web build adds
the commit (linked on Gitea), its date as a tooltip and a "+" when built
from a tree with uncommitted changes (build_web.py writes a
<meta name="isokit-build"> from GITHUB_SHA or git). /api/meta now carries
"engine". studio/favicon.svg (isometric cube in the accent green) is
served by `isokit studio` (also on /view) and copied into the web build.
check_web.py and check_studio.py check both.

crates/isokit-project/src/api.rs

@@ -18,6 +18,7 @@ pub fn meta<S: Store>(ws: &Workspace<S>) -> Value {
     v["dir"] = json!(ws.dir.display().to_string());
     v["load_error"] = json!(ws.load_error);
     v["script_error"] = json!(ws.project.runtime.as_ref().err());
+    v["engine"] = json!(env!("CARGO_PKG_VERSION"));
     v
 }
 

crates/isokit-project/src/assets.rs

@@ -10,6 +10,7 @@ pub const PAGE: &str = include_str!("../../../viewer/page.html");
 pub const STUDIO_HTML: &str = include_str!("../../../studio/index.html");
 pub const STUDIO_JS: &str = include_str!("../../../studio/studio.js");
 pub const STUDIO_CSS: &str = include_str!("../../../studio/studio.css");
+pub const STUDIO_FAVICON: &str = include_str!("../../../studio/favicon.svg");
 
 /// Asset by its path in the repository ("viewer/isokit-view.js",
 /// "studio/studio.js"), from disk when `ISOKIT_ASSETS` is set.
@@ -26,6 +27,7 @@ pub fn get(path: &str) -> Option<Cow<'static, str>> {
         "studio/index.html" => STUDIO_HTML,
         "studio/studio.js" => STUDIO_JS,
         "studio/studio.css" => STUDIO_CSS,
+        "studio/favicon.svg" => STUDIO_FAVICON,
         _ => return None,
     };
     Some(Cow::Borrowed(s))