fix(safe-fs): compare device views in Worker runtimes

[kamilio]

Device views fail in browser/Worker runtimes when an injected filesystem omits optional stable identity metadata. For example, tree --noreport / exits 1 at /dev with custom comparison authorities require Node context, preventing the shell from listing its virtual null device.

Register the device view's internal comparison fallback, matching the existing mount view pattern. Device stats still establish alias identity; comparisons without sufficient evidence remain unknown. Custom backend callbacks retain their existing Worker restriction. No Node shim or synthetic backing-file identity is introduced.

Regression coverage runs the native graph and bundles both browser and workerd module selections, checking both comparison directions, device aliases, distinct devices, and cancellation. The real Workerd shell reproduction changed from exit 1 to exit 0, listing /dev/null with empty stderr after applying the same one-line registration to an isolated copy of the published bundle.

Validation:

Check	Result
Safe-fs build closure	Passed
Complete safe-fs test suite	81 files, 3,473 tests passed
Package type check and changed-file ESLint	Passed
Actual local Workerd shell before/after	Reproduced failure; fixed run passed

The portable regression failed under both browser and workerd selection before the fix.

Screenshots

Local Worker regression: actual before/after results rendered in Chat; no model run.

[kamilio]

Cherry-picked the portable device comparison fix as 7e4772a.

Verified on remote main at 4da2a66 after local validation and final installed-package qualification. Closing after cherry-pick/reconciliation rather than merging obsolete branch history.

Release is in progress: https://github.com/poe-platform/poe-code/actions/runs/34500155547 ; scoped packages: https://github.com/poe-platform/poe-code/actions/runs/34500155125 .