feat: add Phase 5 Progression & Analytics — smart suggestions, dashboard, schedule

Add auto-progression engine (ProgressionService) with rep increase, weight
increase, deload, and felt-easy acceleration rules. Add AnalyticsService for
user stats, exercise progress charts, and volume-by-day data. New dashboard
and schedule routes with Chart.js visualizations. Progression badges shown
inline on workout day view. Navigation updated with Dashboard and Schedule links.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/templates/partials/progression_badge.html

@@ -0,0 +1,11 @@
+{% if suggestion and suggestion.progression_type != "no_program" %}
+<div style="background: rgba(99, 102, 241, 0.1);
+            border-left: 3px solid var(--pico-primary);
+            padding: 0.5rem 1rem;
+            margin-bottom: 0.5rem;
+            border-radius: 0 0.25rem 0.25rem 0;">
+    <small>
+        <strong>Suggestion:</strong> {{ suggestion.message }}
+    </small>
+</div>
+{% endif %}