reorder sidebar and fix code annotations in headings

- Reorder Language Specification sidebar items per requirements
- Rename Functions to Built-in Functions
- Add backticks around code in headings (UNION ALL, RANK, etc.)

Author: claude

docs/language-spec/functions/window/dense_rank.md

@@ -57,7 +57,7 @@ WHERE owner = 'stackql'
 ORDER BY contributions DESC;
 ```
 
-### Compare DENSE_RANK with RANK and ROW_NUMBER
+### Compare `DENSE_RANK` with `RANK` and `ROW_NUMBER`
 
 ```sql
 -- Compare RANK vs DENSE_RANK vs ROW_NUMBER for contributors

docs/language-spec/functions/window/rank.md

@@ -55,7 +55,7 @@ WHERE owner = 'stackql'
   AND repo = 'stackql';
 ```
 
-### Compare RANK with DENSE_RANK and ROW_NUMBER
+### Compare `RANK` with `DENSE_RANK` and `ROW_NUMBER`
 
 ```sql
 -- Compare RANK vs DENSE_RANK vs ROW_NUMBER for contributors
@@ -70,7 +70,7 @@ WHERE owner = 'stackql'
   AND repo = 'stackql';
 ```
 
-### Rank contributors within each repository using PARTITION BY
+### Rank contributors within each repository using `PARTITION BY`
 
 ```sql
 -- Rank contributors within each repo

docs/language-spec/functions/window/row_number.md

@@ -69,7 +69,7 @@ WHERE owner = 'stackql'
 ORDER BY created_at;
 ```
 
-### Compare ROW_NUMBER with RANK and DENSE_RANK
+### Compare `ROW_NUMBER` with `RANK` and `DENSE_RANK`
 
 ```sql
 -- Compare RANK vs DENSE_RANK vs ROW_NUMBER for contributors

docs/language-spec/with.md

@@ -86,7 +86,7 @@ FROM weekly_totals
 ORDER BY week;
 ```
 
-### Combining data from multiple sources with UNION ALL
+### Combining data from multiple sources with `UNION ALL`
 
 CTEs are useful for combining data from multiple sources before performing analysis.
 

sidebars.js

@@ -46,26 +46,26 @@ const sidebars = {
       label: 'Language Specification',
       items: [
         'language-spec/select',
-        'language-spec/with',
-        'language-spec/windowing_functions',
         'language-spec/insert',
         'language-spec/update',
-        'language-spec/replace',
         'language-spec/delete',
+        'language-spec/replace',
         'language-spec/show',
         'language-spec/describe',
         'language-spec/exec',
         'language-spec/createview',
         'language-spec/refreshview',
-        'language-spec/dropview',        
+        'language-spec/dropview',
+        'language-spec/with',
         'language-spec/registry',
+        'language-spec/windowing_functions',
         {
           type: 'category',
-          label: 'Functions',
+          label: 'Built-in Functions',
           items: [{type: 'autogenerated', dirName: 'language-spec/functions'}]
-        },        
-        'language-spec/lexical-structure',
+        },
         'language-spec/data-types',
+        'language-spec/lexical-structure',
         'language-spec/keywords',
         'language-spec/utility-commands',
       ]