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

tests/sample_data/pug/test/anti-cases/attrs.unescaped.pug

@@ -0,0 +1,3 @@
+script(type='text/x-template')
+  #user(id!='user-<%= user.id %>')
+    h1 <%= user.title %>

tests/sample_data/pug/test/anti-cases/case-when.pug

@@ -0,0 +1,4 @@
+when 5
+  .foo
+when 6
+  .bar

tests/sample_data/pug/test/anti-cases/case-without-with.pug

@@ -0,0 +1,2 @@
+case foo
+  .div

tests/sample_data/pug/test/anti-cases/else-condition.pug

@@ -0,0 +1,4 @@
+if foo
+  div
+else bar
+  article

tests/sample_data/pug/test/anti-cases/else-without-if.pug

@@ -0,0 +1,2 @@
+else
+  .foo

tests/sample_data/pug/test/anti-cases/inlining-a-mixin-after-a-tag.pug

@@ -0,0 +1 @@
+foo()+bar()

tests/sample_data/pug/test/anti-cases/key-char-ending-badly.pug

@@ -0,0 +1 @@
+div("foo"abc)

tests/sample_data/pug/test/anti-cases/key-ending-badly.pug

@@ -0,0 +1 @@
+div(foo!~abc)

tests/sample_data/pug/test/anti-cases/mismatched-inline-tag.pug

@@ -0,0 +1,2 @@
+//- #1871
+p #[strong a}

tests/sample_data/pug/test/anti-cases/mixin-args-syntax-error.pug

@@ -0,0 +1,2 @@
+mixin foo(a, b)
++foo('a'b'b')

tests/sample_data/pug/test/anti-cases/mixins-blocks-with-bodies.pug

@@ -0,0 +1,3 @@
+mixin foo
+  block
+    bar

tests/sample_data/pug/test/anti-cases/multiple-non-nested-tags-on-a-line.pug

@@ -0,0 +1 @@
+foo()bar

tests/sample_data/pug/test/anti-cases/non-existant-filter.pug

@@ -0,0 +1,2 @@
+:not-a-valid-filter
+  foo bar

tests/sample_data/pug/test/anti-cases/non-mixin-block.pug

@@ -0,0 +1,2 @@
+div
+  block

tests/sample_data/pug/test/anti-cases/open-brace-in-attributes.pug

@@ -0,0 +1 @@
+div(title=[)

tests/sample_data/pug/test/anti-cases/readme.md

@@ -0,0 +1 @@
+This folder collects examples of files that are not valid `pug`, but were at some point accepted by the parser without throwing an error.  The tests ensure that all these cases now throw some form of error message (hopefully a helpful one).

tests/sample_data/pug/test/anti-cases/self-closing-tag-with-block.pug

@@ -0,0 +1,2 @@
+input
+  | Inputs cannot have content

tests/sample_data/pug/test/anti-cases/self-closing-tag-with-body.pug

@@ -0,0 +1 @@
+input Input's can't have content

tests/sample_data/pug/test/anti-cases/self-closing-tag-with-code.pug

@@ -0,0 +1 @@
+input= 'Inputs cannot have code'

tests/sample_data/pug/test/anti-cases/tabs-and-spaces.pug

@@ -0,0 +1,3 @@
+div
+  div
+	article

tests/sample_data/pug/test/anti-cases/unclosed-interpolated-call.pug

@@ -0,0 +1 @@
++#{myMixin

tests/sample_data/pug/test/anti-cases/unclosed-interpolated-tag.pug

@@ -0,0 +1,4 @@
+mixin item
+  block
+
++item( Contact

tests/sample_data/pug/test/anti-cases/unclosed-interpolation.pug

@@ -0,0 +1 @@
+#{myMixin