fix-nested-code-fenceslisted

# Skill: fix-nested-code-fences When a code block contains inner triple-backtick fences, replace the outer fence with `~~~` — the minimum change that fixes rendering without altering any content. **Don't:** change inner fences — only the outer fence needs replacing. Don't apply this to tilde fences that are already correct. ## The Problem When markdown is generated or written that contains code block examples inside other code blocks, the inner fences terminate the outer block early, breaking rendered output. Common in: skill templates, documentation generators, README examples, any file where markdown is shown inside markdown. ## The Fix Replace the **outer** fence with `~~~` when the block contains inner ` ``` ` fences. Inner fences stay as-is. **Before:** ```` ```markdown ## Example ```bash VAR=value ``` ``` ```` **After:** ~~~~ ~~~markdown ## Example ```bash VAR=value ``` ~~~ ~~~~ ## Steps 1. Read the file 2. Find any fenced code block that contains inner ` ``` ` fences 3. Replace the outer opening and closing fences with `~~~` 4. Leave inner fences unchanged 5. Confirm the fix and offer to commit if in a git repo