feat(labs): visual polish wave — LabFX foundation + 33 sims juiced up

ФУНДАМЕНТ (4 новых файла):
- _fx_core.js: LabFX namespace, glow.drawGlow, glow.pulse, haptic, shake
- _fx_particles.js: пул 1500 объектов, 6 shapes (dot/spark/ring/smoke/splash/dust)
- _fx_motion.js: tween + 12 easings + critically-damped spring
- _fx_sound.js: 9 procedural synth-звуков (click/tick/whoosh/chime/fizz/spark/bounce/pour/drone), Web Audio API
- Sound toggle в шапке lab.html с localStorage-persist

UX МИКРО (CSS + JS):
- Button states: hover scale+brightness, active scale-down, disabled grayscale
- Slider polish: custom thumb с тенью, filled-track gradient, hover/active
- Focus rings через :focus-visible
- Tooltip system .tt-host data-tt= с 400ms hover, fade-in
- Marching ants для selection
- Loading skeleton с shimmer
- Empty state .sim-empty-* паттерн
- Toast: progress bar внизу, icons по типу
- Cursor states utility classes
- View Transitions API для smooth sim-switch, fallback на CSS fade

PHASE 2 — визуальные эффекты для 33 симуляций:

Physics motion: projectile (launch whoosh + landing splash/shake/haptic + target chime), pendulum (max-extension tick + bob glow), collision (bounce + sparks + shake), angrybirds (whoosh/bounce/fizz/chime + confetti), newton (rocket flame trail + scene transitions), forcesandbox (spring glow + impact sparks)

Physics fields: emfield (field-lines glow + particle trail + lightning при high field + Gauss-drag haptic + rod motion sparks), circuit (energized-wire glow ∝ current + LED bloom + short-circuit shake/spark + heat shimmer smoke + place/erase/switch sounds), opticsbench (beam glow на всех режимах + caustics dust у фокуса + TIR/Brewster one-shot sounds)

Thermo+waves: waves (mode-switch whoosh + Mach-cone particles + spectrum harmonic chime + waveform glow), hydrostatics (pour sound + splash при погружении + valve click), isoprocess (PV-trail dust), heatengine (drone цикла + hot/cold reservoir smoke/dust + phase-change ticks), radioactive (Geiger tick throttle + decay sparks + half-life chime + α/β/γ glow)

Chemistry: chemsandbox (pour splash + fizz bubbles/dust/spark по типу реакции + shake при горении), equilibrium/electrolysis/reactions/titration/flask/ionexchange/redox (pour/fizz/spark/chime по событиям, частицы при ключевых моментах), stoichiometry (fizz bubbles + recipe-change click)

Math+geom: geometry (tool-click + object-create tick + locus glow + challenge confetti via LabFX + haptic), triangle (vertex-drop tick + special-point glow), stereo (figure-change whoosh + cross-section chime, no particles — Three.js), trigcircle (drag-haptic + pitch∝angle tick + sin/cos glow), graph/graphtransform/quadratic (slider-tick throttled + curve glow + discriminant-cross chime), probability (bounce + finish-chime burst), normaldist (pulsing shade + bell glow)

Bio+misc: celldivision (phase-change whoosh + prophase dust + anaphase poles spark + cytokinesis chime), photosynthesis (photon tick + ATP chime + glucose sparkle), bohratom (electron-jump chime ∝ levels + photon spark), orbitals/crystal (mode-change whoosh — Three.js, sound only), logic (gate-place + wire-connect + LED bloom + HIGH wire flowing dots + preset chime), gas/brownian/diffusion/states (preset whoosh, throttled tick по событиям)

Все LabFX вызовы обёрнуты в if (window.LabFX) guard — graceful degradation если фундамент не загружен. 47 JS файлов прошли syntax check.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/js/labs/forcesandbox.js

@@ -178,6 +178,8 @@ class ForceSandboxSim {
       forces: [],
     };
     this.bodies.push(body);
+    /* LabFX: spawn sound */
+    if (window.LabFX) LabFX.sound.play('click', { pitch: 1.3 });
     return body;
   }
 
@@ -602,10 +604,11 @@ class ForceSandboxSim {
   /* ── Tick ─────────────────────────────────────────────────── */
 
   _tick(now) {
-    let dt = Math.min((now - this._last) / 1000, 0.05);
+    let rawDt = Math.min((now - this._last) / 1000, 0.05);
     this._last = now;
+    if (window.LabFX) LabFX.particles.update(rawDt);
     if (this._paused) { this.draw(); return; }
-    dt *= this.timeScale;
+    const dt = rawDt * this.timeScale;
     this._simTime += dt;
     this._step(dt);
     this.draw();
@@ -1183,6 +1186,15 @@ class ForceSandboxSim {
     if (!a.pinned) this._applyImpulse(a, -J, nx, ny, rAx, rAy);
     if (!b.pinned) this._applyImpulse(b,  J, nx, ny, rBx, rBy);
     const keAfter = 0.5 * a.mass * (a.vx * a.vx + a.vy * a.vy) + 0.5 * b.mass * (b.vx * b.vx + b.vy * b.vy);
+    /* LabFX: body collision */
+    if (window.LabFX && J > 0.5) {
+      LabFX.sound.play('bounce');
+      LabFX.particles.emit({
+        ctx: this.ctx, x: cx, y: cy,
+        count: 8, color: '#FFF', speed: 60,
+        spread: Math.PI * 2, life: 300, shape: 'spark', glow: true,
+      });
+    }
     this._energyLoss += Math.max(0, keBefore - keAfter) / (S * S);
 
     // Трение между телами
@@ -1393,7 +1405,11 @@ class ForceSandboxSim {
     if (this.ramp)      this._drawRamp(ctx);
     if (this.showTrail) this._drawTrails(ctx);
     this._drawRopes(ctx);
-    this._drawSprings(ctx);
+    if (window.LabFX && this.springs.length > 0) {
+      LabFX.glow.drawGlow(ctx, () => this._drawSprings(ctx), { color: '#9B5DE5', intensity: 4 });
+    } else {
+      this._drawSprings(ctx);
+    }
     this._drawBodies(ctx);
     if (this.showForces)   this._drawForceArrows(ctx);
     if (this.showVelocity) this._drawVelocities(ctx);
@@ -1402,6 +1418,8 @@ class ForceSandboxSim {
     if (this.showEnergy)   this._drawEnergyBar(ctx);
     if (this._ghostPos && !this._drag && !this._hovered && this.tool !== 'erase') this._drawGhost(ctx);
     if (this.bodies.length === 0) this._drawHint(ctx);
+    /* LabFX: particles overlay */
+    if (window.LabFX) LabFX.particles.draw(this.ctx);
   }
 
   _drawBg(ctx, W, H) {