Fix hydration, placeholders, and variable font geometry

vendor/cosmic-text/Cargo.toml

@@ -42,7 +42,6 @@ fontconfig = [
 ]
 monospace_fallback = []
 no_std = [
-    "rustybuzz/libm",
     "hashbrown",
     "dep:libm",
 ]
@@ -129,8 +128,7 @@ version = "1.1.0"
 default-features = false
 
 [dependencies.rustybuzz]
-version = "0.14"
-features = ["libm"]
+version = "0.20"
 default-features = false
 
 [dependencies.self_cell]
@@ -158,7 +156,7 @@ version = "0.3.1"
 optional = true
 
 [dependencies.ttf-parser]
-version = "0.21"
+version = "0.25"
 default-features = false
 
 [dependencies.unicode-bidi]