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>

simulator/app.py

@@ -120,6 +120,15 @@ def create_app(manifest_path: Optional[Path] = None) -> FastAPI:
         )
         return ring_move_to_dict(move, app.state.ring)
 
+    @app.middleware("http")
+    async def _no_cache(request, call_next):
+        # Dev preview server: never let a browser serve a stale app.js/style.css.
+        # The whole point is by-eye iteration, so a plain refresh must always get
+        # the latest assets (the heuristic cache otherwise hides JS/CSS edits).
+        response = await call_next(request)
+        response.headers["Cache-Control"] = "no-cache, no-store, must-revalidate"
+        return response
+
     if MEDIA_DIR.exists():
         app.mount("/media", StaticFiles(directory=MEDIA_DIR), name="media")
     if STATIC_DIR.exists():