Fix uncontrolled recursion in WKBGeometryBounder::MergeGeometryInternal

[wgtmac]

Added a depth limit (128) to MergeGeometryInternal to prevent stack overflow (Denial of Service) when parsing maliciously crafted, deeply nested WKB GeometryCollection inputs. A unit test TestWKBBounderErrorForDeepNesting has been included to ensure proper exception throwing upon exceeding the limit.

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PR created automatically by Jules for task 6705798834579741264 started by @wgtmac

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