feat(dashboard): implement reactive tracker-dashboard integration

Replaced surface-level "disabled" messages with true reactive integration.
When tracker editor saves config changes, dashboard now automatically
updates without page reload - removing disabled widgets and refreshing
remaining ones with new field names/settings.

**Event-Based Architecture:**
- trackerEditor.js dispatches 'rpg:trackerConfigChanged' custom event
- dashboardManager.js subscribes to event and reacts to changes
- Decoupled, extensible, browser-native event system

**Dashboard Reactive Methods:**
- onTrackerConfigChanged(config): Main handler coordinating refresh flow
- removeDisabledWidgets(config): Removes widgets with disabled fields
  - Cleans up DOM, drag/resize handlers, state
  - Removes from tab.widgets arrays
- shouldWidgetBeRemoved(type, config): Decision logic per widget type
  - calendar → remove if date disabled
  - weather → remove if weather disabled
  - temperature → remove if temperature disabled
  - clock → remove if time disabled
  - location → remove if location disabled
  - userStats → remove only if ALL stats disabled
  - presentCharacters → remove if thoughts disabled
- refreshAllWidgets(): Re-renders all remaining widgets with new config

**Widget Auto-Removal Flow:**
1. User disables field in tracker editor
2. Clicks "Save & Apply"
3. Event fires → dashboard receives notification
4. Disabled widgets removed from all tabs
5. Affected tabs auto-layout to fill space
6. Remaining widgets re-render with new config
7. Layout saved automatically

**Removed Surface-Level Bandaid:**
- Deleted checkFieldEnabled() from infoBoxWidgets.js (-36 lines)
- Removed all checkFieldEnabled() calls from widget renders (-25 lines)
- Removed empty state message from userStatsWidget.js (-8 lines)
- Removed tracker settings link handler (-7 lines)
- Widgets no longer show "⚠️ Field disabled" messages
- Dashboard handles removal elegantly instead

**Result:**
True reactive integration. Disable "Arousal" → instantly disappears from
all userStats widgets. Disable "Date" → calendar widget removed and tab
auto-layouts. Rename "Health" to "HP" → updates instantly everywhere.
All changes happen immediately without page reload.

Files modified:
- src/systems/dashboard/dashboardManager.js (+129 lines)
- src/systems/ui/trackerEditor.js (+11 lines)
- src/systems/dashboard/widgets/infoBoxWidgets.js (-67 lines)
- src/systems/dashboard/widgets/userStatsWidget.js (-21 lines)

src/systems/dashboard/widgets/infoBoxWidgets.js

@@ -12,43 +12,6 @@
  * Users can arrange them independently or group them together.
  */
 
-/**
- * Check if a field is enabled in trackerConfig and render disabled state if not
- * @param {HTMLElement} container - Widget container
- * @param {string} fieldName - Field name in trackerConfig (e.g., 'date', 'weather', 'temperature')
- * @param {string} displayName - Display name for the field (e.g., 'Date', 'Weather')
- * @param {Object} dependencies - Dependencies object
- * @returns {boolean} True if enabled, false if disabled
- */
-function checkFieldEnabled(container, fieldName, displayName, dependencies) {
-    const { getExtensionSettings } = dependencies;
-    const settings = getExtensionSettings();
-    const trackerConfig = settings.trackerConfig?.infoBox;
-    const fieldEnabled = trackerConfig?.widgets?.[fieldName]?.enabled !== false;
-
-    if (!fieldEnabled) {
-        container.innerHTML = `
-            <div class="rpg-widget-empty-state">
-                <p>⚠️ ${displayName} disabled</p>
-                <p style="font-size: 0.85em; opacity: 0.7;">
-                    Enable in <a href="#" class="rpg-open-tracker-settings">Tracker Settings</a>
-                </p>
-            </div>
-        `;
-
-        // Handle tracker settings link
-        const link = container.querySelector('.rpg-open-tracker-settings');
-        if (link) {
-            link.addEventListener('click', (e) => {
-                e.preventDefault();
-                document.getElementById('rpg-open-tracker-editor')?.click();
-            });
-        }
-    }
-
-    return fieldEnabled;
-}
-
 /**
  * Parse Info Box data from shared data source
  * @param {string} infoBoxText - Raw info box text
@@ -236,12 +199,6 @@ export function registerCalendarWidget(registry, dependencies) {
 
         render(container, config = {}) {
             const { getInfoBoxData } = dependencies;
-
-            // Check if date field is enabled in trackerConfig
-            if (!checkFieldEnabled(container, 'date', 'Date', dependencies)) {
-                return;
-            }
-
             const data = parseInfoBoxData(getInfoBoxData());
 
             const monthShort = data.month ? data.month.substring(0, 3).toUpperCase() : 'MON';
@@ -330,12 +287,6 @@ export function registerWeatherWidget(registry, dependencies) {
 
         render(container, config = {}) {
             const { getInfoBoxData } = dependencies;
-
-            // Check if weather field is enabled in trackerConfig
-            if (!checkFieldEnabled(container, 'weather', 'Weather', dependencies)) {
-                return;
-            }
-
             const data = parseInfoBoxData(getInfoBoxData());
 
             const weatherEmoji = data.weatherEmoji || '🌤️';
@@ -368,12 +319,6 @@ export function registerTemperatureWidget(registry, dependencies) {
 
         render(container, config = {}) {
             const { getInfoBoxData } = dependencies;
-
-            // Check if temperature field is enabled in trackerConfig
-            if (!checkFieldEnabled(container, 'temperature', 'Temperature', dependencies)) {
-                return;
-            }
-
             const data = parseInfoBoxData(getInfoBoxData());
 
             const tempDisplay = data.temperature || '20°C';
@@ -415,12 +360,6 @@ export function registerClockWidget(registry, dependencies) {
 
         render(container, config = {}) {
             const { getInfoBoxData } = dependencies;
-
-            // Check if time field is enabled in trackerConfig
-            if (!checkFieldEnabled(container, 'time', 'Time', dependencies)) {
-                return;
-            }
-
             const data = parseInfoBoxData(getInfoBoxData());
 
             const timeDisplay = data.timeEnd || data.timeStart || '12:00';
@@ -471,12 +410,6 @@ export function registerLocationWidget(registry, dependencies) {
 
         render(container, config = {}) {
             const { getInfoBoxData } = dependencies;
-
-            // Check if location field is enabled in trackerConfig
-            if (!checkFieldEnabled(container, 'location', 'Location', dependencies)) {
-                return;
-            }
-
             const data = parseInfoBoxData(getInfoBoxData());
 
             const locationDisplay = data.location || 'Location';