Fix web runtime wake handling and bundle required fonts

[Gratenes]

Summary

Companion runtime changes for zeronsh/zeron#319 (web UI support).

Dispatcher wake handling

Atomics.waitAsync can return synchronously when the signal no longer equals the expected value. The previous mailbox loop treated that result as an error and exited, permanently stopping main-thread work dispatch.

Clear the wake flag before draining queued work, then wait. If work arrives between clearing the flag and waiting, continue the loop on the synchronous result instead of exiting. Asynchronous results still await their promise.

Required font assets

Include the eight IBM Plex Sans and Lilex font files referenced by the web platform, plus their upstream OFL licenses. This lets downstream browser builds resolve the existing embedded font paths without a private asset checkout. Assets and licenses were sourced from Zed revision f14fea9.

Scope

One commit, 11 files: the dispatcher change, eight fonts, and two license files. No native platform implementation changes or standalone example changes.

Validation

• The downstream Zeron web application built successfully with locked dependencies pinned to this published commit (53f49068b7aa2b796360e640b2635dbabba9c032) using nightly-2026-09-08 and Trunk.
• The build used a fresh target/dist pair and no temporary GPUI source paths.
• Font license contents were checked against the upstream source.

This is a draft for early review. A dedicated automated dispatcher race regression is not included, and this is not a claim that the full zui workspace test suite passed. Once these changes land upstream, the companion application can replace its fork dependency pin with the upstream revision.

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