feat: OpenRouter provider routing and reasoning control

[chiefmojo]

Problem

When using OpenRouter as the LLM provider, operators have no way to:

1. Exclude specific upstream providers from serving requests (provider.ignore)
2. Set a preferred provider order (provider.order)
3. Control reasoning effort per model slot (reasoning)

All three are standard OpenRouter-specific request fields that MemOS currently passes through to the HTTP body without any config surface.

Changes

Config schema — adds providerIgnore, providerOrder, and reasoning to LlmSchema and SkillEvolverSchema:

llm:
  provider: openai_compatible
  endpoint: https://openrouter.ai/api/v1
  apiKey: sk-...
  providerIgnore:
    - together
    - deepinfra
  providerOrder:
    - anthropic
    - google
  reasoning:
    enabled: true
    max_tokens: 8000

SkillEvolverSchema:
  provider: openai_compatible
  endpoint: https://openrouter.ai/api/v1
  providerIgnore:
    - novita

Provider layer — openai.ts detects OpenRouter endpoints and injects the provider routing object; reasoning is forwarded unconditionally when set. Non-OpenRouter endpoints are unaffected.

Embedding — providerIgnore/providerOrder added to the embedding config schema; openai.ts embedding provider applies the same routing logic.

Pipeline — bootstrapMemoryCore forwards the new fields to createLlmClient for the skillEvolver slot.

Tests

• providers.test.ts — reasoning forwarding, routing injection for non/streaming calls, non-OpenRouter passthrough
• bootstrap-llm-config.test.ts — verifies routing fields propagate to dedicated LLM clients
• load.test.ts — defaults to empty arrays, accepts explicit values

[Memtensor-AI]

Automated Test Results: PASSED

Cloud test-engine rerun against dev-v2.0.22 completed successfully.

• Run: tr-013a21fe-6ec on cloud test-engine 10011
• memos_local_openclaw/unit: 10 passed, 0 failed, 0 skipped
• memos_local_plugin/unit: 90 passed, 0 failed, 0 skipped

Manual code review is still required before merge.

[Memtensor-AI]

Conflict status update: I verified locally that refs/pull/1958/head cleanly merges with dev-v2.0.22, and the previous cloud test-engine run passed (tr-013a21fe-6ec, 100/100). However, pushing the merge commit back to the PR head failed because the head fork repository is not accessible (Repository not found).

Current conclusion: automated tests passed, but the PR cannot be merged while GitHub still reports it as conflicting. The branch needs to be updated by the author/maintainer, or a replacement branch/PR needs to be created from the locally clean merge commit and then retested.