[Feature]: Add manifest as a provider like gemini/antropic or so

[leonardorey1992]

Summary

Add a provider that manage the api-keys and redirect the calls to proper models like manifest

Problem statement

Im working with manifest at openclaw that is installed like

openclaw plugin install manifest

I'd love it with the zeroclaw approach, repo is here https://github.com/mnfst/manifest

i try with #5730 but never works with cargo and facing problems when builind

What do u think? its feasible? this will give fallback to models and also route properly that i think right now is not happening

Proposed solution

#5730 or similar

Non-goals / out of scope

No response

Alternatives considered

No response

Acceptance criteria

provider is config
able to work with manifest via url config
auto route by manifest

Architecture impact

providers/

Risk and rollback

No response

Breaking change?

No

Data hygiene checks

• I removed personal/sensitive data from examples, payloads, and logs.
• I used neutral, project-focused wording and placeholders.

**NOTE i know it could work with https://github.com/zeroclaw-labs/zeroclaw/wiki/05.2-Custom-Providers but i think it's easier to do with the dropdown :D