Implement advanced graph algorithms

Create implementations for advanced graph algorithms:

## Network flow algorithms:
- Ford-Fulkerson algorithm
- Edmonds-Karp algorithm
- Push-relabel algorithm
- Bipartite matching
- Minimum cost flow

## Connectivity algorithms:
- Strongly connected components (Kosaraju's algorithm)
- Articulation points and bridges
- Eulerian path and circuit
- Hamiltonian path
- Maximum bipartite matching

## Shortest path algorithms:
- A* search algorithm
- Johnson's algorithm
- All-pairs shortest path algorithms
- K shortest paths

## Requirements:
- Provide detailed complexity analysis
- Create visualization helpers
- Include comprehensive test cases
- Document practical applications

This collection will extend the basic graph algorithms with more advanced techniques used in network optimization, robotics, and artificial intelligence.

No files, tests, or entry points are named. Start by reviewing the repository's existing basic graph algorithms, then determine how the requested network flow, connectivity, and shortest-path algorithms should fit alongside them. Done requires the listed algorithms, complexity analysis, visualization helpers, comprehensive tests, and practical-application documentation.

Written by the indexing model from the issue text.