fix(dashboard): hover infobulles, full-width layout, UX polish

- Fix doc tooltips: split CSS into <style type='text/tailwindcss'> for
  @apply directives + raw CSS for reliable doc panel rendering
- Convert doc panels from click-toggle to hover-based infobulles with
  arrow pointer, fade-in animation, and auto-dismiss on mobile
- Replace '?' icons with 'ⓘ' across all 11 templates (51 tooltips)
- Full-width layout: reduce padding on mobile (px-3), scale up on
  desktop (lg:px-5, xl:px-6) for maximum screen utilization
- Auto-collapse sidebar on narrow screens (<1024px)
- Keyboard shortcuts: Alt+1–9 for page navigation, Alt+B toggle sidebar
- Add LEGITIMATE_BROWSER filter button to detections page
- Sticky header with stronger blur (backdrop-blur-md)
- All 46 routes pass tests

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

services/dashboard/backend/templates/features.html

@@ -2,7 +2,7 @@
 {% block title %}JA4 SOC — Features ML{% endblock %}
 {% block page_title %}
     Features ML
-    <span class="relative inline-block ml-1"><button onclick="docToggle(this)" class="doc-btn">?</button><div class="doc-panel">
+    <span class="relative inline-block ml-1"><button onclick="docToggle(this)" class="doc-btn">ⓘ</button><div class="doc-panel">
         <h4>Exploration des features</h4>
         <p>Visualisez les 72 features ML extraites : comportementales (velocity, fuzzing), réseau (port_density, JA4), et thesis §5 (entropie, cadence, drift).</p>
         <p><strong>Radar :</strong> Compare les profils ISP (humain) vs datacenter (bot). <strong>Scatter :</strong> Identifiez visuellement les clusters anormaux.</p>
@@ -16,7 +16,7 @@
     <div class="grid grid-cols-1 lg:grid-cols-2 gap-4">
         <div class="section-card">
             <div class="section-header"><span class="section-title">Profil Humain vs Bot (Radar)
-                <span class="relative inline-block"><button onclick="docToggle(this)" class="doc-btn">?</button><div class="doc-panel">
+                <span class="relative inline-block"><button onclick="docToggle(this)" class="doc-btn">ⓘ</button><div class="doc-panel">
                     <h4>Comparaison ISP vs Datacenter</h4>
                     <p>Profil moyen des sessions ISP (humaines) vs sessions datacenter (bots potentiels). Les axes sont les features ML normalisées.</p>
                     <p><strong>Interprétation :</strong> Plus la zone rouge dépasse la verte, plus la feature est discriminante. hit_velocity, fuzzing_index et post_ratio sont typiquement les plus discriminants.</p>
@@ -27,7 +27,7 @@
         </div>
         <div class="section-card">
             <div class="section-header"><span class="section-title">Importance des features (Variance)
-                <span class="relative inline-block"><button onclick="docToggle(this)" class="doc-btn">?</button><div class="doc-panel">
+                <span class="relative inline-block"><button onclick="docToggle(this)" class="doc-btn">ⓘ</button><div class="doc-panel">
                     <h4>Feature importance</h4>
                     <p>Variance inter-classe (ISP vs datacenter) de chaque feature. Les features à haute variance discriminent le mieux bots et humains.</p>
                     <p><strong>Usage :</strong> Les features en tête sont les plus utiles pour le modèle EIF. Celles à variance nulle sont élaguées automatiquement.</p>
@@ -41,7 +41,7 @@
     <!-- Row 2: Scatter full-width -->
     <div class="section-card">
         <div class="section-header"><span class="section-title">Scatter — Hit Velocity vs Fuzzing Index
-            <span class="relative inline-block"><button onclick="docToggle(this)" class="doc-btn">?</button><div class="doc-panel">
+            <span class="relative inline-block"><button onclick="docToggle(this)" class="doc-btn">ⓘ</button><div class="doc-panel">
                 <h4>Scatter bidimensionnel</h4>
                 <p>Chaque point = une session IP. X = cadence de requêtes, Y = diversité des paths. Les clusters séparés du groupe principal sont des anomalies.</p>
                 <p><strong>Action :</strong> Cliquez sur un point pour ouvrir la page IP détail.</p>