fix(build): regenerate communication bridge for header changes

[voltjia]

Summary

Regenerate the generated communication bridge whenever a source header used by the bridge generator changes. Existing build directories could otherwise retain a stale backend manifest after provider headers were added, removed, or modified.

Changes

• Dependency tracking
  • Track the base, backend, and device headers read by the bridge generator.
  • Generate a stable dependency list so header additions and removals trigger CMake reconfiguration.
  • Add the tracked headers to the bridge custom command dependencies.
• Regression coverage
  • Add a source contract test for the generator dependency graph.
  • Register the contract with CTest.

Platform and Backend Affected

Platform

• CPU
• NVIDIA GPU
• Iluvatar GPU
• MetaX GPU
• Moore Threads GPU
• Cambricon MLU
• HYGON DCU

Backend

• OpenMPI
• MPICH
• NCCL
• MCCL

Performance Impact

• No performance impact
• Performance improved
• Performance regression possible

N/A. This changes build invalidation only.

Known Issues & Future Work

• None.

Test Results

Test environment: ssh nvidia, accelerator-dev/nvidia:latest.

• Clean OpenMPI configure and build passed.
• Touching an existing provider header regenerated the manifest and bridge.
• Adding a provider header triggered CMake glob reconfiguration, regenerated the bridge, and added the provider to the manifest.
• CTest passed.
• ruff check, ruff format --check, and git diff --check passed.

Test Involved Platform

• CPU
• NVIDIA GPU
• Iluvatar GPU
• MetaX GPU
• Moore Threads GPU
• Cambricon MLU
• HYGON DCU

Test Involved Backend

• OpenMPI
• MPICH
• NCCL
• MCCL

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Checklist

Title, Branch, and Commits

• PR title follows Conventional Commits.
• Branch name follows <type>/xxx-yyyy-zzzz.
• Each commit message follows Conventional Commits.
• This small PR is a single squashable commit.
• No stray merge commits from master.
• No fixup! / squash! / wip commits remain.

Scope and Design

• Changes are minimal and contain no unrelated modifications.
• No dead code, debug output, or unowned TODOs were added.
• No unrelated formatting churn was introduced.
• N/A: No public runtime API changes are included.

General Code Hygiene

• Comments are limited to non-obvious intent.
• Every modified or added file ends with a single trailing newline.
• No trailing whitespace, inconsistent indentation, or mixed formatting remains.
• Code identifiers in comments and errors use Markdown backticks where applicable.
• Comments and error messages are in English.
• Comments and error messages follow the repository language conventions.

C++ Specific

N/A: No C++ source file changes are included.

Python Specific

• The regression test is PEP 8 compliant and ruff check passes.
• ruff format --check passes.
• Comments follow the repository conventions.
• Framework-specific conventions are preserved.
• Function body spacing follows the repository conventions.
• Control-flow spacing follows the repository conventions.
• Return statement spacing follows the repository conventions.
• Docstrings follow PEP 257 where applicable.
• Type hints are consistent with surrounding tests.

Testing

• N/A: This build-dependency PR has no runtime example behavior; clean and incremental bridge builds are covered above.

Build, CI, and Tooling

• N/A: No backend or device auto-detection entry is added.
• The applicable Ruff checks pass locally; clang-format is not applicable.

Documentation

• N/A: This fixes internal build invalidation and does not change the user workflow or public behavior.
• N/A: No user-visible breaking change is introduced.

Security and Safety

• No secrets, internal URLs, customer data, or personal hardware identifiers are included.
• No third-party code is introduced.
• No unsafe pointer arithmetic, uninitialized read, or bounds-check change is introduced.