Bump traefik from v3.7.8 to v3.7.9 in /compose/production/traefik

[dependabot]

Bumps traefik from v3.7.8 to v3.7.9.

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

---

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot show <dependency name> ignore conditions will show all of the ignore conditions of the specified dependency
• @dependabot ignore this major version will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this minor version will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)

[claude]

Review

This is a minimal, low-risk Dependabot patch bump: traefik:v3.7.8 → v3.7.9 in compose/production/traefik/Dockerfile. Single line changed, no other files affected.

Assessment:

• Correctness: Straightforward patch version bump within the same major/minor line (v3.7.x). Low risk of breaking changes.
• Security: Patch releases from Traefik typically include bug/security fixes — keeping current is generally beneficial. Worth a quick skim of the v3.7.9 release notes to confirm no relevant CVE or behavior change affects this deployment's config (middlewares, ACME/TLS handling, etc.), since this is the production reverse proxy.
• Test coverage: No tests apply here — this is infra/dependency config, not application code. CI (build) passing is the main correctness signal.
• Risk: Since Traefik terminates TLS and routes production traffic, I'd still recommend confirming CI builds and a smoke test in staging before merge, per standard practice for base image bumps on the production proxy — but the version delta itself is minimal.

No code quality or style concerns — this is auto-generated dependency-update content. Safe to merge once CI is green, consistent with standard Dependabot approval practices for patch-level bumps.