[houko]

The dispatched platform test workflow was failing for four concrete reasons:

• Ubuntu did not install the libsoup runtime required by Linux image HTTP tests.
• TestInitTemplates forced GOPROXY=off, so a fresh runner failed when an uncached transitive x/sys version was needed.
• Desktop pull-to-refresh checked the rubber-banded offset, which kept the documented 64-point threshold unreachable for a normal 140-point pull.
• CoreText's single-line shortcut disagreed with the framesetter for non-ASCII fallback-font runs, including Japanese Menlo text.

This change installs libsoup, keeps generated-app tests isolated without disabling module downloads, measures refresh pulls before rubber-banding on Linux and Windows, and routes non-ASCII single-line text through the framesetter. It adds a regression test for the pull behavior.

Validation:

• go tool nsgo check
• go tool nsgo test ./internal/platform/scrollbar
• go tool nsgo test ./internal/platform/apple
• go tool nsgo test ./cmd/nsgo -run '^TestInitTemplates$'