Add HTML Snippets extension (#3418)

Adds comprehensive HTML snippets extension with 95+ snippets covering
all HTML5 elements.
   
   Features:
   - Complete HTML5 coverage
   - Smart placeholders
   - Semantic elements
   - Form controls
   - Media elements

Author: seekode

.gitmodules

@@ -1066,6 +1066,10 @@
 	path = extensions/html-jinja
 	url = https://github.com/JaagupAverin/html-jinja.git
 
+[submodule "extensions/html-snippets"]
+	path = extensions/html-snippets
+	url = https://github.com/seekode/zed-html-snippets.git
+
 [submodule "extensions/http"]
 	path = extensions/http
 	url = https://github.com/tie304/zed-http.git

extensions.toml

@@ -1083,6 +1083,10 @@ version = "0.2.3"
 submodule = "extensions/html-jinja"
 version = "0.1.0"
 
+[html-snippets]
+submodule = "extensions/html-snippets"
+version = "0.1.0"
+
 [http]
 submodule = "extensions/http"
 version = "0.0.1"