Improve test suite quality and coverage

Test Coverage Improvements:
- Add gtest_basic_types.cpp: Tests for toStr(), convertFromString(), splitString()
- Add gtest_if_then_else.cpp: Tests for IfThenElseNode control node
- Add gtest_while_do_else.cpp: Tests for WhileDoElseNode control node
- Add gtest_loggers.cpp: Tests for StdCoutLogger, FileLogger2, MinitraceLogger, SqliteLogger
- Add decorator tests: ForceFailure, ForceSuccess, Inverter, KeepRunningUntilFailure

Critical Fixes from Test Review:
- Remove debug std::cout statements from gtest_coroutines.cpp and script_parser_test.cpp
- Delete empty unused gtest_scripting.cpp (script_parser_test.cpp provides coverage)
- Fix timing fragility: Replace magic numbers with named constants
- Reduce test durations from 200-500ms to 10-50ms for faster CI execution

All 420 tests pass.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: facontidavide

tests/CMakeLists.txt

@@ -6,13 +6,15 @@ set(BT_TESTS
   src/condition_test_node.cpp
 
   gtest_any.cpp
+  gtest_basic_types.cpp
   gtest_blackboard.cpp
   gtest_coroutines.cpp
   gtest_decorator.cpp
   gtest_enums.cpp
   gtest_factory.cpp
   gtest_fallback.cpp
   gtest_groot2_publisher.cpp
+  gtest_if_then_else.cpp
   gtest_parallel.cpp
   gtest_preconditions.cpp
   gtest_ports.cpp
@@ -21,6 +23,7 @@ set(BT_TESTS
   gtest_match.cpp
   gtest_name_validation.cpp
   gtest_json.cpp
+  gtest_loggers.cpp
   gtest_reactive.cpp
   gtest_reactive_backchaining.cpp
   gtest_sequence.cpp
@@ -31,6 +34,7 @@ set(BT_TESTS
   gtest_tree.cpp
   gtest_updates.cpp
   gtest_wakeup.cpp
+  gtest_while_do_else.cpp
   gtest_interface.cpp
   gtest_simple_string.cpp