Fix broken tests

[thadcraft-shopify]

PRs #380 and #386 worked independently but broke grind tests when merged together. #380 added
configure_lazy_queue to the eager-mode path, setting entry_resolver on all queues including Grind. #386
reordered Static#poll to check entry_resolver before @index. Together, the grind queue's raw test ID strings
(e.g. "ATest#test_flaky") hit JSON.parse in LazyEntryResolver and crash, silently producing no results.

Additionally, even if the entries were JSON-formatted, the overhead of JSON.dump on millions of grind
entries consumed the entire --max-duration budget before any tests could run.

• Override entry_resolver on Grind to be a no-op, since grind always eagerly loads tests and uses the @index
  built by Static#populate
• Fix test_resolve_entry_returns_unresolved_entry_without_index_or_resolver which used an undefined
  DELIMITER constant

[thadcraft-shopify]

• Fix broken tests #389 👈 (View in Graphite)
• main

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