refactor(cmake): split build setup and engine modules

[chamsechan]

The root CMake file mixed compiler setup, dependency acquisition, runtime layer targets, and product assembly; ONNX Runtime and llama.cpp also shared one engine module. Split those responsibilities into ProjectSetup, Dependencies, RuntimeGraph, and ProductTargets, with separate modules for each open-source engine. Move the existing Kite integration into company/ and feed its compile definitions and libraries into the runtime graph through neutral variables.

Preserve the current CMake 3.19 entrypoints, engine pins, checksums, cache locations, and output layout. Company platform/toolchain setup and mirror rules remain outside this stage. Update CI cache keys and documentation, and add a CMake-only structural check for the thin root, company module boundary, dependency aggregation, and include resolution.

Validation:

• Canonical repository gate: 390 passed, 1 optional GGUF test skipped because EDGEFLOW_TEST_LLAMA_GGUF was not supplied.
• Minimal configuration generated successfully; ONNX Runtime + llama.cpp + Whisper SDK compiled and linked successfully.
• Cache publication/import/fallback tests and structural negative checks passed.
• Kite conflict checks passed without loading a package; the real Kite SDK and company target hardware were not exercised.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-12T06:38:14.140024Z	a9e59c7	PR opened

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