SMLib: the prebuilt where a set-back corner's sections are their rounds' exact arcs

Pins tangency-labs/smlib 1072d1b (release prebuilt-1072d1b857de…): an N-sided corner
patch now meets each round on the round's own exact section edge instead of its polynomial
approximation, which the stitch kept on a near tie at some corners (solidcore#1377).
SMLIB_PREBUILT rewritten by scripts/fetch-smlib.sh --pin.

The kernel's tess, display_mesh, step, corner and fillet tests fail the same 63 as with the
previous pin, none new.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/smlib/SMLIB_PREBUILT

@@ -1,10 +1,10 @@
 # Rust target, SHA-256 of smlib-<target>.tar.gz in the release prebuilt-<SMLIB_REV> of
 # tangency-labs/smlib. Written by scripts/fetch-smlib.sh --pin; never edited by hand.
-aarch64-apple-darwin 7b53c2a5278b62c033e2755579e21ad62c406eee80d35ebd11b68c0fa15ca102
-aarch64-pc-windows-msvc b2736b3738272b90e3fd8e240185c5974cc8df6018e76042a4b951ee9c51915d
-aarch64-unknown-linux-gnu e220d61b82d9dca6fec3760d745ffcd0ccb057683aa44c6275cffbdb2d80ba6e
-i686-pc-windows-msvc 90f5513ce1e178b9a3cbdbf2148449eb5ca93b3e1e3c9f5a4b87f6d8a2edb823
-wasm32-unknown-unknown a90e958eced83c4b4413442dfeab68fdb71931b898ffd9f45a6436be2386ace8
-x86_64-apple-darwin 6f503928c3458145d35d66d9ffe7dfa433113d8eeda195cc17dbf0bb95d5128b
-x86_64-pc-windows-msvc 1486d3540cecd85192a3b5e728c5ca36995f642a2425c434a2905d6da9018e05
-x86_64-unknown-linux-gnu c61af3671f5c3aea229fd2f90a853bf2906ba58e4819b0548ced7493344ad606
+aarch64-apple-darwin 1831f4bf25b787a5a37bab95cb48836c73886312e87f0b1a4a29bab013e30433
+aarch64-pc-windows-msvc fd8c3826a0b0f84dd6bef4d66b87280026de11ea1cd16e8d90e688f9b7bc11a3
+aarch64-unknown-linux-gnu ce1a857ea1ab4d27ea9577bf70bd0bf18be6416bb7b1d94107e6d92b9558ca83
+i686-pc-windows-msvc 944dab108f28dadb68ade79389cdb2a5fc9e12d1b0331e8b8692a3180c918efc
+wasm32-unknown-unknown 73d69573edb69de53e873d48587905fad6cc4250e5662be3b404c003401f3327
+x86_64-apple-darwin e819a1fb2d069e59d5ac07995af11952ec0c7ef22642f8e714a5e0e0459d21df
+x86_64-pc-windows-msvc 64cb340c1da2cafda86e42556b1dbec9a93fe28908bf3d2b1ec6cd08e15c658e
+x86_64-unknown-linux-gnu b7a2c3f170116e4ab402bb65c8d4851b9a1967617a5049826d578c4c397a2514

crates/smlib/SMLIB_REV

@@ -1 +1 @@
-5096462223a836bb478eaf161f816346399ef106
+1072d1b857de2b8d012f09565ad54b2432ff4ddc