commercial property policy, property damage, hailstorm, motion to exclude expert testimony, motion for summary judgment, wear and tear exclusion, cosmetic damage exclusion, corrosion exclusion, deterioration exclusion, cosmetic damage exclusion, seepage or leakage exclusion, faulty workmanship exclusion, breach of contract, extra-contractual liability, DTPA, good faith and fair dealing, expert testimony, Federal Rule of Evidence 702, Daubert, concurrent-cause doctrine