fix(data delete): resolve the table name case-insensitively; fail closed (#1027)

[LukasWodka]

What

tracebloc data delete <name> resolved the table name case-sensitively, so a mis-cased name was a silent no-op (exit 0, nothing deleted) — backend#1027.

Fix

• New resolveDeleteTarget — lists the client's datasets (same listDatasetsFn seam data ingest uses) and matches strings.EqualFold, returning the stored spelling. Fails closed (unlike ingest's guard, which fails open because the in-cluster duplicate check backstops it — a destructive delete has no backstop).
• On match: the real spelling flows into PlanTeardown, PodSpecOptions.Table, the confirmation prompt, and error messages — never the raw flag.
• On no match: exit 5 with the request + a hint listing the datasets that do exist (or "no ingested datasets"). Never a silent exit-0 no-op.
• Listing failure → fail closed (exit 4, "refusing to delete" + the underlying error).
• --dry-run reflects the resolution (real name, or a not-found stop).

Test

New data_delete_test.go mirrors the ingest guard tests: mis-cased resolves + tears down the real name; nonexistent → exit 5 + available names; empty client → exit 5; listing error → exit 4 fail-closed. Confirmation / --yes untouched. go build/test/vet/gofmt clean.

Refs backend#1008.

🤖 Generated with Claude Code

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Note

Medium Risk
Changes destructive delete targeting and exit semantics; behavior is safer (confirmed targets, no silent no-ops) but operators/scripts must handle new exit code 5 and stricter exit 4 when listing fails.

Overview
Fixes backend#1027, where tracebloc data delete could exit 0 without deleting anything when the user’s table name didn’t match the cluster’s case-sensitive spelling.

data delete now lists datasets on the client (same listDatasetsFn / EqualFold behavior as data ingest’s destination guard), resolves the stored spelling, and uses that name for the teardown plan, confirmation prompt, and teardown execution—not the raw CLI argument.

Fail-closed behavior for a destructive command: if the dataset list can’t be read → exit 4 (refuse to delete blind); if no name matches → exit 5 with a hint of datasets that do exist (or that the client has none). Command help documents the new exit 5.

Adds data_delete_test.go covering mis-cased resolution, exact match, not-found, empty client, and listing failure.

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