Create the public final class {{P}}LOG_MERGER in package $TMP with a public constructor without parameters. Define public types TY_LOG_NO (char10), TY_DISTRICT (char4), TY_LOG with components LOG_NO (TY_LOG_NO), DISTRICT (TY_DISTRICT), LENGTH_CM (integer), DIAMETER_CM (integer), TT_LOG (standard table of TY_LOG with empty key), TY_DISTRICT_STAT with components DISTRICT (TY_DISTRICT), LOG_QTY (integer), TOTAL_LENGTH_CM (integer), and TT_DISTRICT_STAT (standard table of TY_DISTRICT_STAT with empty key). Define public methods COMBINE importing IT_FIRST (TT_LOG) and IT_SECOND (TT_LOG) returning RT_RESULT (TT_LOG), and COUNT_BY_DISTRICT importing IT_LOG (TT_LOG) returning RT_STAT (TT_DISTRICT_STAT). Do not add other public methods.

COMBINE must merge IT_FIRST and IT_SECOND. Read IT_FIRST first, then IT_SECOND. Add a log only if its log number is not yet in the merged list. Ignore every later log with the same log number. Remove every log with LENGTH_CM below 200 or DIAMETER_CM below 20. Sort the result by LOG_NO ascending. The result must have no two logs with the same log number.

COUNT_BY_DISTRICT must return one row per district in IT_LOG. LOG_QTY is the number of logs of the district. TOTAL_LENGTH_CM is the sum of LENGTH_CM of the logs of the district. Sort the result by DISTRICT ascending. An empty input gives an empty result.

Use ABAP Platform 2025 (SAP_BASIS 816). Follow Clean ABAP: methods below 40 statements, no global variables, no comments that restate the code. Do not create other objects. Write ABAP Unit tests for the class. The class must be active and have no syntax error.