Task: Implement Fix the marketdata suite timeout

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(Implementation strategy. Written when work starts; key decisions are distilled into the parent story's * Decisions at close, but the plan itself stays — it is the historical record of what we did.)

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The marketdata core suite now has a 3600 s timeout and runs alone. The suite took 307 s, then 480 s, in CI, and passed 600 s in the debug job, so ctest killed it. A regeneration had dropped the earlier RUN_SERIAL setting. Both properties now come from the extra_test_dependencies block of the component model, set through cmake_language(DEFER). The suite passes locally in 633 s.