[2026 DevOps] Add canary deployment health probes for the API service

[Nanle-code]

Objective

Probe critical API routes during canary rollout and auto-abort on error budget breach.

Target area

docker-compose and deploy workflow

Acceptance criteria

• The objective is implemented with clear handling for invalid input, unsupported environments, and failure paths.
• Automated tests cover the primary flow, at least one boundary case, and at least one failure case.
• User-facing documentation or developer guidance is updated, including compatibility, security, or migration notes where applicable.
• Pull requests that address this issue must keep the branch free of merge conflicts with the target branch.
• All continuous integration checks must pass before the pull request may be merged; failing, pending, or skipped required checks are not acceptable for merge.

Pull request requirements

• All continuous integration checks must pass before a pull request may be merged.
• The branch must be free of merge conflicts with the target branch at the time of merge.
• Do not request merge with failing workflows, skipped required checks, or unresolved conflicts.

[titilope12]

@titilope12 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello maintainer, i can fix this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @titilope12 to this issue.