Fixed suite-level sharding collapsing to a single shard

Suite-granularity sharding now correctly matches historical test timing using module-qualified names (Module/Suite). Previously, the server grouped timing data by the bare suite name, while the CLI sent names as Module/Suite, so every lookup missed and fell back to a tiny median duration. That caused shard plans to collapse to a single shard regardless of the per-shard duration target. The fix joins suite timing data to module names and keys the timing map on the full Module/Suite name, restoring accurate duration estimates and proper shard distribution. This also prevents same-named suites in different modules from being conflated.