feat(h5): give the dock five independently tweened slots

[AnonymousUser443]

Crossing the 1023/1024 rail breakpoint used to snap the dock: the grid tracks switch discretely, so the five actions jumped together and landed off their own slots. Each action now owns an absolute slot expressed in percentages of the dock box, so left/top/width/height all interpolate and every action travels its own trajectory into the rail.

• Drop grid-template-columns/rows from the dock transition list. Combined with transition-behavior: allow-discrete they wedge Chrome's layout: the main thread stopped answering CDP for 30s+ at the breakpoint.
• Size the bar box and the rail width with absolute lengths. A bar-side percentage kept growing while the rail-side fraction shrank, inflating the box mid-flight until the publish/active chips overlapped.
• Keep transform free for press feedback and move the publish float to top.
• Enlarge the publish label; let the desktop dock and type scale with clamp().
• h5-visual: replace racy rAF sampling with deterministic pause/seek sampling of the running transitions, assert every action interpolates and that the box never grows past the two settled layouts.
• h5-visual: the guest detail assertion demanded an API-fixture ISBN, but the local-first catalogue renders the seeded record with no listing request. Assert the seeded record shows and that no login gate appears.

Verified: miniProgram lint + 54 tests, web lint + 50 tests, H5 build and performance budget, h5-visual 74/74 with 0 diagnostics, WeApp build.