chore: drop source-attribution comments from provider code

Remove "Ported from OmniRoute" and cockpit-tools attribution comments.
User-Agent strings and README/landing credits are left intact.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

open-sse/shared/zedAuth.js

@@ -1,5 +1,4 @@
 // Zed hosted LLM aggregator — auth + model-catalog helpers.
-// Ported from OmniRoute open-sse/shared/zedAuth.ts (plain JS, no TS types).
 //
 // Zed's cloud (cloud.zed.dev) authenticates native apps with a self-generated RSA
 // keypair instead of a registered OAuth client_id/secret: