Summary

• Enable 2 of 4 disabled test files from ARC-001 (Low Test Coverage) Phase 1
• Update test_opentelemetry_adapter.cpp to use Result API patterns
• Fix namespace issues in udp_transport.h

Changes

Enabled Tests

• test_metric_exporters.cpp (19 tests) - Already using correct Result API patterns
• test_opentelemetry_adapter.cpp (16 tests) - Updated to use is_ok() / is_err() patterns

Result API Migration

// Before
EXPECT_TRUE(result);
EXPECT_FALSE(result);

// After
EXPECT_TRUE(result.is_ok());
EXPECT_TRUE(result.is_err());

Fixed Issues

• udp_transport.h: Fixed namespace issues and added using declaration for base class method

Remaining Tests (Not in this PR)

The following tests require significant API implementation and are tracked separately:

• test_health_monitoring.cpp → Issue [TEST] Implement health monitoring API for test_health_monitoring.cpp (ARC-001 Phase 1) #330
• test_fault_tolerance.cpp → Issue [TEST] Implement fault tolerance API for test_fault_tolerance.cpp (ARC-001 Phase 1) #329

Test Results

[==========] 516 tests from 89 test suites ran
[  PASSED  ] 514 tests

Test Plan

• Build tests with -DMONITORING_BUILD_TESTS=ON
• Run ./tests/monitoring_system_tests
• Verify MetricExportersTest (19 tests) passes
• Verify OpenTelemetryAdapterTest (16 tests) passes

Partially resolves #320