feat: add native SQLite aggregation

[trakhimenok]

Summary

• compile DALgo aggregation queries into native SQLite GROUP BY, aggregate, HAVING, ordering, offset, and limit clauses
• preserve DALgo numeric, collation, placeholder, and non-finite result semantics
• add native, streaming, and hash parity coverage

This is stacked on PR #186 for negative projection and consumes the exact DALgo aggregation commit from dal-go/dalgo#174.

Verification

• GOWORK=off go test ./...
• GOWORK=off go vet ./...
• git diff --check
• cross-repository parity and adversarial review completed

WB effort: dtql-group-by-aggregation

[trakhimenok]

Review by unknown@codex@unknown (head ad7dc52b5113)
Reviewed-Head: ad7dc52

Reviewed the exact reconciled head after merging current main. The resolution retains wildcard projection and identity behavior together with aggregation columns, aliases, finite-result validation, and the newer DALgo aggregation pin. Standalone tests, vet, golangci-lint, diff checks, and push hooks pass.