13.19f: review 3's scope; the tab strip's other-tab guard and the divider's second press pinned

TASKS.md

@@ -484,7 +484,10 @@ Reviews for this section ran on codex `gpt-6.1-sol` at `max` (agent `codex-sol`)
   - 13.19e work: `70318de`'s tests pass. Mutants: the field's deferred finish on a mouse press, both ways, caught; `committedPoints` at twice the spacing, without its last-point term, without `kept`, caught, and its `<=` and its one-pixel floor survived until rows for exactly the spacing and a small brush were added, now caught. `WarpFailureTests` (new, a binary of its own) starves a Liquify dab's scratch (skipped with its warning), Smudge's carried colour and Liquify's offsets (each `ExportError(render)`); each guard's removal caught; the untouched copy's null check is equivalent under starvation (the offsets after it are twice its size). `blurSample` drops Swift's dead `if let` on the mask and `?? 0` for the document. The 13.16 line named `compositor.rendering`; it is `omaphoto.rendering`. 330 of 330 at `-j8`.
   - 13.19e review: round 1 FAIL: the starvation tests took any `ExportError` kind; no test made the Move bar's deferred finish run by itself; AGENTS still called allocating Liquify's buffers for every mode equivalent. Fixed: both tests compare the kind (`encode` and `tooLarge` mutants caught), `aValueLeftByMouseForAnotherFieldApplies` clicks Y with no canvas press (dropping the deferred finish caught), the AGENTS line says caught.
   - 13.19e round 2: PASS.
-  - [ ] 13.19f The fixes since `81894f7` already tested (`382c9c2` for 13.9a and 13.9b, `6735aad` for 13.7, 13.14 and 13.15, `5c8e18c` for 13.17 and 13.18) reviewed: review 3's scope.
+  - [x] 13.19f The fixes since `81894f7` already tested (`382c9c2` for 13.9a and 13.9b, `6735aad` for 13.7, 13.14 and 13.15, `5c8e18c` for 13.17 and 13.18) reviewed: review 3's scope.
+  - 13.19f work: the three commits' tests pass. Mutants on their code: the tab strip's release watch (its button test, its start, its ending, its other-tab guard) and the glow's whole steps. The other-tab guard (Swift's `guard reorder?.id == id`) survived; `anotherTabPressedBeforeTheWatchMovesNothing` now catches it. The glow's rounded-up small sides are equivalent (the padded sides are whole steps).
+  - 13.19f review: round 1 FAIL: `aDoubleClickInTheStripMovesADivider` pressed twice at one place, so a double click that skipped the divider passed. Now the first click and the double click land apart; that mutant is caught.
+  - 13.19f round 2: PASS.
   - [ ] 13.19g The full suite under `ctest -j16`; the shared state behind the five parallel failures found and isolated.
   - [ ] 13.19h The acceptance run and its shots.
   - [ ] 13.19i Distro checks: arch, fedora, fedora44, nixos, resolute.