rewrite-list: always return a sample of rules, not just the count #113

Problem

"List Rewrite Rules" returns only "Found 272 rewrite rules" with no actual rules shown.

Reported by @wpbullet in #56.

Root cause

The PHP backend has a show_details parameter that defaults to false. Without it, only rules_count and permalink_structure are returned — no actual rule patterns. The LLM never passes show_details: true because the system prompt only shows the tool description, not input parameters.

Verified via Ollama round-trip test:

• LLM sends: {"action": "tool_call", "tool": "wp-agentic-admin/rewrite-list", "args": {}}
• PHP returns: { rules_count: 272, permalink_structure: "/%postname%/" } (no rules)
• LLM answers: "Found 272 rewrite rules with permalink structure /%postname%/."

Proposed fix

Remove the show_details flag and always return a useful sample of rules. With 272 rules and a 2000-char tool result truncation limit, returning all rules would overflow. Instead:

1. Always include top ~20 rules grouped by pattern type (post, page, category, tag, feed, sitemap, etc.)
2. Include a category summary — e.g., "45 post rules, 12 category rules, 8 feed rules..."
3. Remove the show_details parameter — it adds complexity the LLM can't use

// Always return a sample of rules grouped by type
$result['rule_sample'] = array_slice( $rules_array, 0, 20 );
$result['rule_categories'] = $categorized_counts; // e.g., ['post' => 45, 'page' => 12, ...]

Files to modify

• includes/abilities/rewrite-list.php — remove show_details, always return sample + categories

Refs

Closes #56