fix(highlight): complete markdown syntax highlighting with injections

Fix markdown code block highlighting to properly support both markdown
structure (headings, frontmatter) and language injection (rust, bash).

The key fix uses `#set! injection.include-children` in the injection
query to override tree-sitter-md's internal tokenization, enabling
proper highlighting of embedded languages within code fences.

Changes:
- Use crate's HIGHLIGHT_QUERY_BLOCK for base markdown highlighting
- Add custom injection query with include-children directive
- Add YAML/TOML frontmatter and HTML block injection rules
- Add text.* highlight names (title, literal, uri, reference)
- Add string.escape highlight name
- Add CSS styles for new highlight classes
- Remove unused custom md-highlights.scm

docs/static/style.css

@@ -208,6 +208,29 @@ pre code {
   color: #ff79c6;
 }
 
+/* Markdown-specific text highlighting */
+.hl-text-title {
+  color: #ff79c6;
+  font-weight: bold;
+}
+
+.hl-text-literal {
+  color: #8be9fd;
+}
+
+.hl-text-uri {
+  color: #8be9fd;
+  text-decoration: underline;
+}
+
+.hl-text-reference {
+  color: #bd93f9;
+}
+
+.hl-string-escape {
+  color: #ffb86c;
+}
+
 /* Section navigation */
 .section-nav {
   display: flex;

queries/md-highlights.scm

@@ -1,35 +0,0 @@
-; Minimal markdown block highlighting - only capture outside code blocks
-; Removed all captures that could match inside code_fence_content
-
-(atx_heading (inline) @text.title)
-(setext_heading (paragraph) @text.title)
-
-[
-  (atx_h1_marker)
-  (atx_h2_marker)
-  (atx_h3_marker)
-  (atx_h4_marker)
-  (atx_h5_marker)
-  (atx_h6_marker)
-  (setext_h1_underline)
-  (setext_h2_underline)
-] @punctuation.special
-
-(fenced_code_block_delimiter) @punctuation.delimiter
-(info_string (language) @string)
-
-(link_title) @string
-(link_destination) @text.uri
-(link_label) @text.reference
-
-[
-  (list_marker_plus)
-  (list_marker_minus)
-  (list_marker_star)
-  (list_marker_dot)
-  (list_marker_parenthesis)
-  (thematic_break)
-] @punctuation.special
-
-(block_quote_marker) @punctuation.special
-(backslash_escape) @string.escape

queries/md-injections.scm

@@ -1,7 +1,24 @@
-; Markdown injection queries - testing include-children directive
+; Markdown injection queries with include-children directive
+; Enables proper highlighting of embedded languages in code blocks and frontmatter
 
+; Fenced code blocks - inject language specified in info string
 (fenced_code_block
   (info_string
     (language) @injection.language)
   (code_fence_content) @injection.content
   (#set! injection.include-children))
+
+; YAML frontmatter (--- delimited at start of document)
+((minus_metadata) @injection.content
+  (#set! injection.language "yaml")
+  (#set! injection.include-children))
+
+; TOML frontmatter (+++ delimited)
+((plus_metadata) @injection.content
+  (#set! injection.language "toml")
+  (#set! injection.include-children))
+
+; HTML blocks
+((html_block) @injection.content
+  (#set! injection.language "html")
+  (#set! injection.include-children))

src/highlight.rs

@@ -25,9 +25,14 @@ const HIGHLIGHT_NAMES: &[&str] = &[
     "punctuation.delimiter",
     "punctuation.special",
     "string",
+    "string.escape",
     "string.special",
     "string.special.path",
     "string.special.uri",
+    "text.literal",
+    "text.reference",
+    "text.title",
+    "text.uri",
     "type",
     "type.builtin",
     "variable",
@@ -57,9 +62,14 @@ const HTML_ATTRS: &[&[u8]] = &[
     b" class=\"hl-punctuation-delimiter\"",
     b" class=\"hl-punctuation-special\"",
     b" class=\"hl-string\"",
+    b" class=\"hl-string-escape\"",
     b" class=\"hl-string-special\"",
     b" class=\"hl-string-special-path\"",
     b" class=\"hl-string-special-uri\"",
+    b" class=\"hl-text-literal\"",
+    b" class=\"hl-text-reference\"",
+    b" class=\"hl-text-title\"",
+    b" class=\"hl-text-uri\"",
     b" class=\"hl-type\"",
     b" class=\"hl-type-builtin\"",
     b" class=\"hl-variable\"",
@@ -189,7 +199,7 @@ static MARKDOWN_CONFIG: LazyLock<HighlightConfiguration> = LazyLock::new(|| {
     make_config(
         tree_sitter_md::LANGUAGE.into(),
         "markdown",
-        include_str!("../queries/md-highlights.scm"),
+        tree_sitter_md::HIGHLIGHT_QUERY_BLOCK,
         include_str!("../queries/md-injections.scm"),
     )
 });