docs(rotsq): clarify provenance wording in header comment

The header referenced the license identifier of a third-party library's
bundled dependency while explaining that the implementation deliberately
does not use that library. License scanners match the bare identifier
string and misclassify the file. Reword to state provenance directly:
written from the published papers, nothing vendored or derived.
Comment-only change; also picks up the formatter pass on this file.

Signed-off-by: Martin Vogel <martin.vogel.tech@gmail.com>

src/semantic/rotsq.h

@@ -3,7 +3,9 @@
  *
  * Implements the core of Extended RaBitQ (Gao et al., SIGMOD 2024/2025;
  * arXiv:2405.12497, arXiv:2409.09913) without the reference library (which is
- * C++ and bundles Eigen/MPL-2.0). Named rotsq, not rabitq: this is the
+ * C++ and bundles the Eigen linear-algebra dependency; nothing here is vendored
+ * or derived from it — this file is written from the papers). Named rotsq, not
+ * rabitq: this is the
  * FAMILY core (randomized rotation + per-vector scalar quantization + exact
  * code-expansion estimator), not the papers' exact codebook construction —
  * the name should not overclaim fidelity. Rotate each vector with a deterministic
@@ -34,10 +36,10 @@
 #include <stdint.h>
 
 enum {
-    CBM_RSQ_IN_DIM = 768,   /* input dimension (CBM_SEM_DIM) */
-    CBM_RSQ_DIM = 1024,     /* padded pow2 rotation dimension */
-    CBM_RSQ_BITS = 4,       /* bits per coordinate */
-    CBM_RSQ_LEVELS = 15,    /* (1 << CBM_RSQ_BITS) - 1 */
+    CBM_RSQ_IN_DIM = 768,                 /* input dimension (CBM_SEM_DIM) */
+    CBM_RSQ_DIM = 1024,                   /* padded pow2 rotation dimension */
+    CBM_RSQ_BITS = 4,                     /* bits per coordinate */
+    CBM_RSQ_LEVELS = 15,                  /* (1 << CBM_RSQ_BITS) - 1 */
     CBM_RSQ_CODE_BYTES = CBM_RSQ_DIM / 2, /* two 4-bit codes per byte */
 };