fix: add scoped error logging for lexer/parser errors

- Add std.log.scoped(.pugz) to template.zig and view_engine.zig
- Log detailed error info (code, line, column, message) when parsing fails
- Log template path context in ViewEngine on parse errors
- Remove debug print from lexer, use proper scoped logging instead
- Move benchmarks, docs, examples, playground, tests out of src/ to project root
- Update build.zig and documentation paths accordingly
- Bump version to 0.3.1

benchmarks/templates/search-results.pug

@@ -0,0 +1,17 @@
+.search-results.view-gallery
+  each searchRecord in searchRecords
+    .search-item
+      .search-item-container.drop-shadow
+        .img-container
+          img(src=searchRecord.imgUrl)
+        h4.title
+          a(href=searchRecord.viewItemUrl)= searchRecord.title
+        | #{searchRecord.description}
+        if searchRecord.featured
+          div Featured!
+        if searchRecord.sizes
+          div
+            | Sizes available:
+            ul
+              each size in searchRecord.sizes
+                li= size