Refactor mkconcore.py into a modular build system

[avinxshKD]

The mkconcore.py script has grown into a monolithic 1200+ line file that handles critical build logic for multiple platforms (Windows, POSIX, Docker), graph parsing, and code generation for various languages (Python, C++, Verilog, Matlab).

Current Issues:

• Monolithic Structure: All logic (graph parsing, file I/O, script generation) is mixed in a single linear execution floww
• Hard Maintenance: Adding support for a new language or platform requires modifying multiple scattered sections of the script
• Fragile String Generation: Shell scripts and batch files are generated via extensive string concatenation, which is error-prone
• Implicit Dependencies: The script relies on hardcoded path resolutions and specific file naming conventions that are brittle

Proposed Changes: Refactor mkconcore.py into a modular package structure, separating concerns:

• Builder Class: Abstract base class for platform-specific builders (DockerBuilder, PosixBuilder, WindowsBuilder).
• GraphParser Class: Dedicated class for parsing GraphML and extracting node/edge metadata
• ScriptGenerator Class: Logic for generating run/build/stop scripts, replacing string concatenation with templates (e.g., using jinja2 or cleaner string formatting),
• Encapsulation: Move global variables and constants into a configuration class or module

This refactoring will significantly improve testability and extensibility. It involves rewriting/moving ~1200 lines of code but should preserve exact functionality.

Verification:, Existing tests in tests/test_cli.py cover the end-to-end flow via the CLI and should pass without modification after refactoring

[avinxshKD]

@pradeeban working on the fix, pls let me know if this issue makes sense, thanks

[pradeeban]

Please no. :) This is the core of concore protocol. Any modification of this scale will be a huge undertaking and risk.