[ShuhaoZhangTony]

Overview

Carry the bounded native attention/source-drain observation hooks onto synchronized main af5f9302d9e2a11bd0fe728dde769ada4e523126, preserving every upstream worker statement. This is the forward integration of the exact tested-lineage publication in #57; that checkpoint remains immutable.

Claims

• Add opt-in source collectors and exact finished-request drain; the added worker hook runs after actual InputBatch removal.
• Preserve the existing nonformal classification and all bounded receipt/source checks. No formal H3/H4, numerical-quality, physical-KV, or performance claim is introduced.
• Add parent API process identity binding before plugin loading.

Validation

• Real three-way merge of original base/observation/current worker: no conflict. Removing only the added hook yields the exact current-main worker AST.
• python -m pytest --noconftest tests/plugins_tests/test_ecpa_plugin_evidence.py -q -o addopts='': 27 passed, using the existing development interpreter and runtime dependency set.
• Repository ruff check/format and SPDX/forbidden-import checks pass for changed modules. Repository-configured mypy with --follow-imports=silent: 7 affected protocol modules pass; the initial exact-source PR's 50 mypy errors remain preserved in its original failed run.
• Current-main NPU integration has not been executed. The earlier real TP2 source-drain HTTP observation used the original frozen lineage and cannot be relabeled as validation of this revision. Exact-head GitHub pre-commit run 38690596347 completed successfully (both pre-run-check and pre-commit jobs). The source integration is authorized for merge; rebuilding and actual NPU qualification remain separate pending gates.

Details

The original Host/Ascend source lineage was pinned before main synchronization. A whole-tree reset would lose current upstream work, so this commit reapplies only the 15 required file changes. Among existing touched files, current test/CLI/input-processor blobs still match the old base; only gpu_model_runner required a three-way merge. The delta retains its true finished-request removal point. Newly integrated protocol modules receive source headers, repository formatting/import conventions, and annotations for heterogeneous validated wire records and the dynamically injected NPU backend. No proof check is weakened.

Open-PR duplication audit: #53 concerns accepted KV transfer descriptors, while #8 concerns admission reservation. This change covers the distinct frozen attention/request drain path; #57 is its immutable old-lineage source publication, not a second proposed current-main integration.

The scope is fresh bounded eager TP2 diagnostic observation, not MRV2 feature support or a production inference/performance extension. Explicit synchronization and artifact I/O occur only in the opt-in observation path. New-main hardware/overhead validation remains pending.

---

Pull Request Checklist

• I used vLLM's /pr-checklist skill.
• AI assistance was used during the creation of this PR (Codex).
• Design Fit: Minimal core call sites; the opt-in diagnostic logic remains isolated in plugin modules.
• Testing and Validation: Local protocol/type/style checks pass; exact-current-main NPU integration is pending and is not replaced by historical evidence.
• Code Quality and Style: Source headers, formatting/import conventions and dynamic callback typing addressed without weakening checks.
• Pull Request Contents: Original lineage, true test scope and missing hardware evidence are explicit.