chore(camera): trim lens comment walls and dead build marker

app/src/main/java/io/github/stozo04/openloop/camera/CameraManager.kt

@@ -159,13 +159,9 @@ class CameraManager(private val context: Context) {
                     analysis = analysis,
                 )
                 attachZoomObserver()
-                // The build marker suffix is the stale-APK tripwire (Lesson 012's environment
-                // notes): a logcat whose bind lines lack it was made by a build without the
-                // flick feature, whatever the checkout says.
                 Log.i(
                     TAG,
-                    "Camera bound (lens=${if (lensFacing == CameraSelector.LENS_FACING_BACK) "back" else "front"}) " +
-                        "build=hand-flick-v1"
+                    "Camera bound (lens=${if (lensFacing == CameraSelector.LENS_FACING_BACK) "back" else "front"})"
                 )
 
                 onCameraReady()

app/src/main/java/io/github/stozo04/openloop/camera/lens/FaceRoster.kt

@@ -29,19 +29,10 @@ import kotlin.math.hypot
  *
  * ## ID churn
  *
- * When ML Kit loses a face for a frame or two it often re-detects it under a **new** tracking id.
- * The old id is still being held, so without care the same person would wear two lenses for up to
- * [holdMs] — and, with the slots full, the new id would be locked out until the hold expired. So
- * the nearest fresh face that has no slot and stands within [SAME_FACE_RADIUS_UNITS] of a
- * held-but-unseen slot holder is taken to be that person. A different person cannot land on the
- * exact same spot inside a third of a second, and a third person entering anywhere else during
- * someone's blink still cannot steal a slot.
- *
- * The adopted face is **published under the original id**, not the detector's new one (Lesson
- * 037). Every per-face consumer downstream — the wobble springs and eased mouth in [LensMotion],
- * anything added later — keys its state on [FaceSnapshot.trackingId], so a label change that
- * leaked through would reset all of it mid-blink. The new id is recorded as an alias and folded
- * back onto the original on every later sighting, for as long as that person is held.
+ * ML Kit often re-detects a briefly lost face under a new tracking id. The roster adopts the
+ * nearest fresh face within [SAME_FACE_RADIUS_UNITS] of a held-but-unseen slot as the same person,
+ * publishing it under the original id (Lesson 037) so downstream per-face state keyed on
+ * [FaceSnapshot.trackingId] is not reset mid-blink.
  */
 class FaceRoster(private val maxFaces: Int, private val holdMs: Long) {
 

app/src/main/java/io/github/stozo04/openloop/camera/lens/Lens.kt

@@ -34,27 +34,9 @@ import io.github.stozo04.openloop.R
  * | eye line down to the **chin** | **1.75** |
  * | mouth width, at rest | 0.8 |
  *
- * These are **measured off a real tracked face**, not assumed. An earlier version reasoned them
- * from published head statistics (treating one unit as the interpupillary distance) and every lens
- * came out ~20% oversized — eye-to-mouth is the larger of the two spans. If a lens ever needs
+ * These are **measured off a real tracked face**, not assumed. If a lens ever needs
  * resizing, re-measure against this table rather than nudging a lens in isolation.
  *
- * ## The chin row was wrong until 2026-08-16, and it shipped two bugs
- *
- * This table used to say **chin = 1.00** — which is the same number as the mouth, and that
- * coincidence is the tell: the row was the *mouth* wearing the chin's label. A real jaw runs about
- * another **0.75 units** below the mouth (stomion→menton ≈ 50 mm against a ≈ 67 mm pupil→stomion
- * face unit), putting the chin at **-1.75**.
- *
- * [PizzaFace] and [Football] were both sized against the wrong number, so both stopped at roughly
- * the mouth and left the subject's real chin — and the corners of their real mouth — on show below
- * the art. That is what "the mouth looks duplicated" was: the character's composited mouth *and*
- * the subject's own, at once. [Broccoli] was never affected because it hangs a stalk far below the
- * jaw and covers to -3.88 regardless.
- *
- * `LensAnchorTest.characterLensesCoverTheWholeHead` now asserts crown-to-chin coverage for every
- * character lens, so the class of bug cannot come back silently.
- *
  * Because they are ratios of the face to itself, one set of numbers holds for every face at every
  * distance and angle — there is nothing here to re-tune per device.
  */

app/src/main/java/io/github/stozo04/openloop/camera/lens/LensAnchor.kt

@@ -410,12 +410,8 @@ object LensAnchor {
     }
 
     /**
-     * Resolves the three features to lift onto a character: left eye, right eye, mouth.
-     *
-     * Sources follow the subject's real landmarks (so a blink, a smile and a head turn all carry
-     * through); destinations are fixed points in the face frame (so the character's face does not
-     * inherit the subject's proportions, camera perspective, or a lens-distorted nose). That split
-     * is the whole trick — expression from the human, geometry from the character.
+     * Resolves the three features to lift onto a character. Expression from the human (real
+     * landmarks), geometry from the character (fixed points in the face frame).
      */
     fun features(
         face: FaceSnapshot,

app/src/main/java/io/github/stozo04/openloop/camera/lens/LensSurfaceProcessor.kt

@@ -783,12 +783,6 @@ class LensSurfaceProcessor(context: Context) : SurfaceProcessor {
 
         /**
          * Camera pass — a straight sample of the external OES texture through CameraX's transform.
-         *
-         * This used to carry up to two radial bulges (Big Mouth, Bug Eyes). Both lenses are gone,
-         * and with them the flip into y-down screen space they needed: the shader converted
-         * `vTexCoord`, warped, and converted back, which is exactly the identity when no warp
-         * fires. A lens that deforms pixels again wants that scaffolding back — it is in the
-         * history, not commented out here.
          */
         const val CAMERA_FRAGMENT_SHADER = """
             #extension GL_OES_EGL_image_external : require