fix(webstrap): stub Sparkle query params in web shell

[zhuziqi97]

Summary

• Add a no-op appUpdates.setSparkleQueryParams() implementation to the Linux Web Shell app-host RPC.
• Add regression coverage for the generated app-host RPC surface.
• Fixes Upstream canary failed: prod web-browser-shell 26.715.21425 #51.

Root cause

Upstream prod build 26.715.21425 (build 5488) calls:

ki.appUpdates?.setSparkleQueryParams({ planType: o })

The Linux Web Shell exposed appUpdates, but did not implement
setSparkleQueryParams. Optional chaining guarded only appUpdates, so the
missing method caused:

TypeError: ki.appUpdates?.setSparkleQueryParams is not a function

Behavior

Linux Web Shell does not have a native Sparkle updater. The new method is
therefore an intentional no-op that preserves RPC compatibility without
changing update behavior.

Validation

• node --test test/web-assets.test.mjs — 12 passed
• node --test test/*.test.mjs — 96 passed
• Cached prod build 26.715.21425 / build 5488 smoke — all checks passed
• Full prod canary build — 11/11 checks passed, including web-browser-shell

npm test also discovers ignored generated tests under dist/ and stage/;
those contain six pre-existing missing generated server-module failures. The
controlled repository test suite passes.