Avoid false unsupported-operation telemetry for nested timestamps

[prathamesh-db]

Description

Parses Arrow's epoch-microsecond representation for nested TIMESTAMP and TIMESTAMP_NTZ values before trying the formatted-string converter. Successful numeric values therefore no longer construct and export a false UNSUPPORTED_OPERATION error. Formatted timestamp strings and returned timestamp values are unchanged.

Testing

The regression test covers both timestamp types, a pre-1970 value, microsecond precision, and verifies that successful numeric parsing never initializes the telemetry client.

• mvn spotless:apply: passed
• Focused Maven tests were attempted after rebasing, but current main dependencies were unavailable because Maven Central DNS resolution failed locally. CI remains the current test gate.

Telemetry Errors

• Not applicable — this PR does not add or change a telemetry-visible error.
• Applicable — this removes an incorrect UNSUPPORTED_OPERATION emission; it adds no error code or numeric value.
• Applicable — the existing classification is unchanged; maintainer confirmation is requested that no dashboard or taxonomy update is needed.

Additional Notes to the Reviewer

Review focus: numeric-first fallback behavior and the no-telemetry regression assertion.

NO_CHANGELOG=true