Follow-up from #1080. /jobs/match is 503-gated by JOB_MATCH_ENABLED and the default is OFF in production today. With the current code, every visit to the Matches tab returns 503 and surfaces a generic "Failed to load matches" instead of the backend's intentional product copy.

Two acceptable fixes (per spec)

Option A — hide the tab until the flag is on (recommended).

• On first jobs-page mount, POST /jobs/match once and inspect the response.
• If 503 with code: "SERVICE_UNAVAILABLE", cache the verdict in component state and don't render the Matches tab button at all.
• Surface resume scoring + tailoring on the Jobs page in its place.

Option B — render the 503 message verbatim.

• Fix JobMatch.tsx:33 — the 503 body is {error: {code, message, request_id}}. The current code does errData.error || "Failed to load matches" which renders [object Object] or falls back to the generic string.
• Read errData.error?.message and render it directly. The text is intentional product copy: "Job matching is not yet available. We're sourcing real postings; in the meantime use /jobs/resume/score for resume coaching."

Acceptance

• A user with the flag off either does not see a Matches tab, or sees the operator-friendly message — never a generic error.
• The fix doesn't break behavior once the flag flips on.