add lock for concurrently writing to map

[huangzhen1997]

Fix concurrent write to the same map. Slack reference. Jira

[Copilot]

Pull Request Overview

This PR adds mutex locks to protect concurrent writes to shared maps in three view fetcher functions, preventing race conditions when multiple goroutines write to the same map simultaneously.

Key Changes:

• Added sync.Mutex to synchronize concurrent map writes in parallel goroutine execution
• Applied mutex locking pattern consistently across router, onramp, and fee quoter view functions

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
deployment/view/router.go	Added mutex protection for concurrent writes to onRampAddrMap
deployment/view/onramp.go	Added mutex protection for concurrent writes to output map in fetchDestChainConfig
deployment/view/feequoter.go	Added mutex protection for concurrent writes to output map in fetchDestChainConfigsView

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