Add assertion messages to .toThrow() calls to unblock oxlint 1.70 upgrade

oxlint 1.70 enables `vitest/require-to-throw-message` by default, which flags 24 pre-existing `.toThrow()` / `.rejects.toThrow()` calls that assert no message. The oxlint bump was held at 1.62.0 in the latest dependency update so this surfaced separately rather than blocking routine bumps.

Add a matcher argument (string or regex) to each call so the assertions verify *which* error is thrown, then bump oxlint to 1.70+ (currently latest) and drop the hold.

## Affected files (24 sites)

| File | Count |
| --- | --- |
| `packages/graph-explorer/src/connector/sparql/parseAndMapQuads.test.ts` | 11 |
| `packages/graph-explorer/src/connector/sparql/fetchNeighbors/index.test.ts` | 4 |
| `packages/graph-explorer/src/connector/queries/edgeConnectionsQuery.test.ts` | 3 |
| `packages/graph-explorer/src/connector/queries/schemaSyncQuery.test.ts` | 1 |
| `packages/graph-explorer/src/connector/sparql/neighborCounts.test.ts` | 1 |
| `packages/graph-explorer/src/connector/sparql/rawQuery.test.ts` | 1 |
| `packages/graph-explorer/src/connector/fetchDatabaseRequest.test.ts` | 1 |
| `packages/graph-explorer/src/core/StateProvider/localDb.test.ts` | 1 |
| `packages/graph-explorer-proxy-server/src/server.test.ts` | 1 |

## Done when

- Every flagged `.toThrow()` asserts a specific message/pattern
- oxlint bumped to 1.70+ and the 1.62.0 hold removed from root `package.json`
- `pnpm run checks` passes

Related: #1753 (enabling other disabled oxlint rules)

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