feat(sim): analytical Left HUD redesign + affect channel + no-cache

Left-brain HUD look-and-feel pass (judged by eye in the sim):
- corner-bracket targeting reticles (capped arms) replace plain boxes
- translucent label chips, legible over any frame
- two sensor channels: cyan detections (with deterministic confidence
  scores) vs amber measurements (center crosshair)
- bbox-sized "ANALYSIS . L{n} . {k} OBJ" status tag, escalating with Left

Affect channel (emotions in the HUD), per
docs/superpowers/specs/2026-06-22-affect-channel-hud-design.md:
- surfaces only when BOTH knobs up; strength = min(left, right)
- stable per-scene palette, more words appear with combined strength
- soft glowing violet words on their own opacity layer (the dream
  leaking into the machine's read); math in player/alteration.py
- forest/cosmos/abyss palettes in the manifest; 5 new unit tests

Simulator no-cache middleware so by-eye iteration never serves a stale
app.js / api response (fixes the latent "plan has affect but clip.affect
empty" stale-/api/clips bug).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

player/alteration.py

@@ -85,6 +85,18 @@ class AnalyticalOverlay:
     intensity: float
 
 
+@dataclass(frozen=True)
+class AffectOverlay:
+    """Affect channel (Left x Right): emotion-words surfaced only when BOTH the
+    analytical (Left) and dreamlike (Right) knobs are up. `strength` is
+    `min(left, right)` (0..4) — a runtime affect track picks which feeling words
+    appear by it; `intensity` 0..1 is their opacity. The dream leaking into the
+    machine's reading (affect-channel design, session 0013)."""
+
+    strength: int
+    intensity: float
+
+
 @dataclass(frozen=True)
 class Restyle:
     """Right axis (§4.1): selects a pre-baked, flow-stabilized restyle variant.
@@ -99,11 +111,14 @@ class RenderPlan:
 
     grade: ColorGrade
     overlay: AnalyticalOverlay
+    affect: AffectOverlay
     restyle: Restyle
 
     @property
     def is_identity(self) -> bool:
-        """True when the plan leaves the neutral base un-altered."""
+        """True when the plan leaves the neutral base un-altered. Affect needs no
+        clause: `min(left,right) > 0` implies `left > 0`, so `overlay.level > 0`
+        already makes a plan with active affect non-identity."""
         return (
             self.grade.is_identity
             and self.overlay.level == 0
@@ -115,6 +130,15 @@ def _overlay_intensity(left: int, cal: Calibration) -> float:
     return _clamp(cal.overlay_gain * left / KNOB_MAX, 0.0, 1.0)
 
 
+def _affect_strength(left: int, right: int) -> int:
+    """Affect surfaces only when BOTH knobs are up — gated by the smaller one."""
+    return min(left, right)
+
+
+def _affect_intensity(left: int, right: int, cal: Calibration) -> float:
+    return _clamp(cal.overlay_gain * _affect_strength(left, right) / KNOB_MAX, 0.0, 1.0)
+
+
 def _right_variant(right: int, cal: Calibration) -> int:
     return cal.right_variant_map[right]
 
@@ -133,6 +157,10 @@ def plan_alteration(
             level=coord.left,
             intensity=_overlay_intensity(coord.left, calibration),
         ),
+        affect=AffectOverlay(
+            strength=_affect_strength(coord.left, coord.right),
+            intensity=_affect_intensity(coord.left, coord.right, calibration),
+        ),
         restyle=Restyle(variant=_right_variant(coord.right, calibration)),
     )
 
@@ -142,6 +170,7 @@ def render_plan_to_dict(plan: RenderPlan) -> dict:
     return {
         "grade": {"tone": plan.grade.tone},
         "overlay": {"level": plan.overlay.level, "intensity": plan.overlay.intensity},
+        "affect": {"strength": plan.affect.strength, "intensity": plan.affect.intensity},
         "restyle": {"variant": plan.restyle.variant},
         "is_identity": plan.is_identity,
     }