feat: add structured skills parsing with categories and levels

Add AI tracker awareness for skills system with proper level and category support.

Changes:
- Add extractSkills() parser function to extract structured skills data
  - Parses category-based format: "CategoryName:\n- SkillName (Lv X)"
  - Falls back to legacy string format for backward compatibility
  - Returns structured data: { version: 1, categories: {}, uncategorized: [] }

- Update prompt instructions to request structured skills format
  - AI now generates: "Skills:\nCombat:\n- Swordsmanship (Lv 5)"
  - Supports multiple categories (Combat, Magic, Social, Crafting, etc.)
  - Includes Uncategorized section for skills without clear category

- Add buildSkillsSummary() utility function
  - Converts structured skills data back to formatted text
  - Ready for future feature: syncing manual skill edits to AI context

Parser integration:
- parseUserStats() now uses extractSkills() to parse Skills section
- Stores structured data in extensionSettings.userStats.skills
- Widget reads structured data for display and level-up/down functionality

AI workflow:
1. AI generates skills in structured format (via prompt instructions)
2. Parser extracts to structured data (via extractSkills)
3. Widget displays with level controls (already implemented)
4. Raw text flows through committedTrackerData to next generation

Note: Manual skill edits (level-up/down in widget) are not yet synced back
to AI context. This requires additional work to regenerate the raw text
when skills are manually modified. buildSkillsSummary is ready for this.

Refs: Skills widget implementation (previous session)

src/systems/generation/parser.js

@@ -133,6 +133,88 @@ function debugLog(message, data = null) {
     }
 }
 
+/**
+ * Extract structured skills data from stats text
+ * Parses format:
+ * Skills:
+ * CategoryName:
+ * - SkillName (Lv X)
+ * - SkillName (Lv X)
+ * Uncategorized:
+ * - SkillName (Lv X)
+ *
+ * @param {string} statsText - Stats section text containing skills
+ * @returns {Object|null} Structured skills data or null if not found
+ */
+function extractSkills(statsText) {
+    if (!statsText) return null;
+
+    // Find the Skills section
+    const skillsMatch = statsText.match(/Skills:([\s\S]*?)(?=\n\n|On Person:|Stored|Assets:|Main Quest|Optional Quest|$)/i);
+    if (!skillsMatch) {
+        // Fallback: try simple format "Skills: skill1, skill2"
+        const simpleMatch = statsText.match(/Skills:\s*(.+)/i);
+        if (simpleMatch) {
+            const skillsText = simpleMatch[1].trim();
+            if (skillsText && skillsText !== 'None') {
+                // Return as string for backward compatibility
+                return skillsText;
+            }
+        }
+        return null;
+    }
+
+    const skillsSection = skillsMatch[1];
+    const skillsData = {
+        version: 1,
+        categories: {},
+        uncategorized: []
+    };
+
+    // Split into lines and process
+    const lines = skillsSection.split('\n').map(line => line.trim()).filter(line => line);
+
+    let currentCategory = null;
+
+    for (const line of lines) {
+        // Check if this is a category header (ends with colon, no dash)
+        if (line.endsWith(':') && !line.startsWith('-')) {
+            currentCategory = line.slice(0, -1).trim();
+            if (currentCategory !== 'Uncategorized' && !skillsData.categories[currentCategory]) {
+                skillsData.categories[currentCategory] = [];
+            }
+            continue;
+        }
+
+        // Check if this is a skill line (starts with -, has level info)
+        const skillMatch = line.match(/^-\s*(.+?)\s*\(Lv\s*(\d+)\)/i);
+        if (skillMatch) {
+            const skillName = skillMatch[1].trim();
+            const level = parseInt(skillMatch[2], 10) || 1;
+
+            const skill = {
+                name: skillName,
+                level: level,
+                xp: 0,
+                maxXP: 100
+            };
+
+            if (currentCategory === 'Uncategorized' || currentCategory === null) {
+                skillsData.uncategorized.push(skill);
+            } else if (currentCategory && skillsData.categories[currentCategory]) {
+                skillsData.categories[currentCategory].push(skill);
+            }
+        }
+    }
+
+    // Return null if no skills were found
+    if (Object.keys(skillsData.categories).length === 0 && skillsData.uncategorized.length === 0) {
+        return null;
+    }
+
+    return skillsData;
+}
+
 /**
  * Parses the model response to extract the different data sections.
  * Extracts tracker data from markdown code blocks in the AI response.
@@ -351,10 +433,12 @@ export function parseUserStats(statsText) {
         // Parse skills section if enabled
         const skillsConfig = trackerConfig?.userStats?.skillsSection;
         if (skillsConfig?.enabled) {
-            const skillsMatch = statsText.match(/Skills:\s*(.+)/i);
-            if (skillsMatch) {
-                extensionSettings.userStats.skills = skillsMatch[1].trim();
-                debugLog('[RPG Parser] Skills extracted:', skillsMatch[1].trim());
+            const skillsData = extractSkills(statsText);
+            if (skillsData) {
+                extensionSettings.userStats.skills = skillsData;
+                debugLog('[RPG Parser] Skills extracted:', skillsData);
+            } else {
+                debugLog('[RPG Parser] Skills extraction failed or none found');
             }
         }