ZCode Plan Bridge v0.5.1 — DSH engine metadata

Version 0.5.1 moves the existing DSH compatibility range from nested dsh.engines.dsh to the top-level engines.dsh read by the host and catalog. The range, model forwarding and authorization behavior are unchanged.

Validation: 43 tests passed, typecheck and whitespace checks passed. The packed manifest passes the installed DSH 0.2.1-rc.3 host compatibility evaluator. The package contains 12 files, including the runtime, diagnostic CLI, Cordis patch and license.

For DSH Desktop, download the .tgz and use Extensions → Plugin Management → Add Plugin. Existing 0.6.0-community.* preview users should retain that version: stable 0.5.x does not contain the preview's unlimited-retry implementation. This release does not downgrade the local preview, change Desktop configuration, or claim a new live model test.

Source: #4, commit 8a7ec7364dffd8c8c468ce8cbcae26cc716a9c5a. Published from this reviewed diff with user authorization; the PR remains unmerged. No npm publication was performed.

SHA-256: 3f4dcdc38a4faf3f3bd197474c06466126e287357b51a64d818f9e084ff44342.

v0.5.0 — 跟上双内核升级（ZCode CLI 3.16.3 + DSH 0.2.1-rc.3）

桥同时耦合两个内核，这次两边一起跟上来。