fix(core): ignore unsupported agent colors - #57910

Issue for this PR

Fixes #54057

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

Problem. V1 accepted theme color names (primary, accent, warning, …) for an agent's color. V2 only accepts six-digit hex. An agent file like this one has only keys V2 knows, so it is read as V2, the color fails validation, and the whole agent is silently dropped. In one report this removed 8 of 9 custom agents. The same applies to agents.<name>.color in opencode.json, where it failed the config.

---
description: demo agent
mode: subagent
color: accent
---

Change. An invalid color is now ignored instead of rejecting the agent. The agent loads with its default color.

 Config.Agent
-  color: hex                     # invalid → whole agent rejected
+  color: hex, or ignored         # invalid → color omitted, agent kept

Builds on #54257 by @4sDriven, which maps the theme names to hex. This keeps the change to the schema field only. Valid hex colors are unchanged, and the published config JSON schema and generated client are unchanged.

How did you verify your code works?

From packages/core:

bun test test/config     # 249 pass, 0 fail
bun typecheck

The new agent-file case fails without the change. The existing rejects named agent color tokens test now checks that a named color is dropped while the rest of the agent is kept. I also checked that packages/schema typechecks and its tests pass, that the generated config.json schema is byte-identical, and that bun run generate in packages/client produces no changes.

Screenshots / recordings

No UI changes.

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR