[Feat] Remember routing preferences in Brain

[roomote-roomote]

​Opened on behalf of @daniel-lxs. Follow up by mentioning @roomote-roomote, in the web UI, or in Slack.

What changed

• Store each user's routing preference as an exact, deterministic page in the existing Brain.
• Learn strong signals from explicit corrections and weaker signals from accepted routing confirmations across Slack, Discord, and Telegram.
• Fetch preference memory in parallel with normal routing context and apply it only as a decaying tie-breaker for ambiguous environment choices.
• Preserve configured owner/repository references and GitHub URLs as explicit routing signals that memory cannot override.
• Keep preference reads and writes fail-open with a 500 ms bound, and exclude auto-confirmed and all-repository routes from learning.

Why this change was made

Repeated routing corrections should improve future ambiguous task routing without adding another memory system, semantic retrieval, or an extra router model turn.

Impact

Roomote can remember explicit environment preferences across tasks while preserving explicit environment names, configured repository references, and confident router decisions as the authoritative signals. Deployments without Brain configured continue through the existing routing path without an additional network call.

[roomote-community]

No code issues found. See task

• Preserve explicit configured repository references when applying routing memory (packages/cloud-agents/src/server/router/router-service.ts:182).

_{Reviewed 3e7b06b}

[roomote-roomote]

Fixed in 3e7b06b: configured owner/repository references and GitHub URLs now remain explicit routing signals that Brain memory cannot override. Added focused coverage for repo-qualified issue references and issue URLs. See task.