fix: use bracket placeholders in output-format to match codebase convention

Change {count}/{n} to [total]/[count] in the output-format block.
The {…} syntax is used for resolvable variables in BMAD workflows,
while editorial-review-structure.xml uses [X]/[N] for output-format
placeholders.

src/core/tasks/review-adversarial-general.xml

@@ -45,8 +45,8 @@
       <output-format>
         ## Adversarial Review Findings
 
-        **Findings:** {count}
+        **Findings:** [total]
-        - Critical: {n} | High: {n} | Medium: {n} | Low: {n}
+        - Critical: [count] | High: [count] | Medium: [count] | Low: [count]
 
         1. **{SEVERITY}** - `{location}` - {description}
         2. **{SEVERITY}** - {description}