Enhancement test coverage

[rxdu]

No description provided.

[Copilot]

Pull Request Overview

This pull request significantly enhances test coverage by adding comprehensive edge case and error condition testing across multiple core components. The changes add 53 new test cases covering SearchContext functionality, DFS/BFS algorithms, and advanced graph operations, while also standardizing CI coverage reporting across different lcov versions.

• Add comprehensive SearchContext testing including custom attributes, cost types, and path reconstruction
• Add extensive DFS and BFS algorithm testing covering null graphs, disconnected components, cycles, and performance scenarios
• Add advanced graph operations testing for complex topologies, vertex removal, and neighbor operations

Reviewed Changes

Copilot reviewed 11 out of 12 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/unit_test/search_context_comprehensive_test.cpp	New comprehensive SearchContext tests (12 test cases)
tests/unit_test/dfs_comprehensive_test.cpp	New DFS edge case and error condition tests (10 test cases)
tests/unit_test/bfs_comprehensive_test.cpp	New BFS comprehensive tests including shortest path verification (16 test cases)
tests/unit_test/advanced_graph_operations_test.cpp	New advanced graph operations tests (9 test cases)
include/graph/search/bfs.hpp	Added TraverseAll and IsReachable utility methods
tests/CMakeLists.txt	Updated to include new test files
.github/workflows/ci.yml	Standardized lcov commands across CI environments
docs/coverage_notes.md	Added documentation for CI coverage standardization
TODO.md	Updated progress documentation
include/graph/impl/*.hpp	Added required iostream includes

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[Copilot]

[nitpick] The manual BFS implementation duplicates logic that exists elsewhere in the codebase. Consider refactoring to reuse existing BFS search logic with a custom goal predicate instead of implementing a separate traversal.

Suggested change

	// Use unified search logic with a goal predicate that never succeeds
	auto goal_predicate = [](const auto&) { return false; };
	auto visit_callback = [&](const auto& vertex_it) {
	auto& info = context.GetSearchInfo(vertex_it);
	info.SetChecked(true);
	};
	// Use BFS strategy
	SearchAlgorithm<State, Transition, StateIndexer>::template Search<BfsStrategy<State, Transition, StateIndexer>>(
	graph, context, start, goal_predicate, visit_callback);