feat(ovhcloud): add reasoning options

[rekram1-node]

Summary

• audit all 15 active OVHcloud chat models against the official OVHcloud catalog
• add exact reasoning controls to all 6 reasoning models: one documented toggle and five fixed/non-configurable declarations
• preserve authored reasoning options during OVHcloud sync and cover the behavior with focused regression tests

Verification

• bun test packages/core/test/ovhcloud-sync.test.ts packages/core/test/sync-runner.test.ts
• bun validate
• bun models:sync ovhcloud (15 unchanged)
• git diff --check

Audit notes

• OVHcloud documents /no_think for Qwen3-32B, represented as a toggle.
• OVHcloud does not document configurable effort values or token budgets for the other reasoning models, so they use empty options.
• No OVHcloud API credential was available for authenticated probes; the public catalog endpoint was queried live.