fix(serve): emit all stream_chunk deltas to fix concurrent tool-call streaming

[lvhan028]

The following is test script
test_concurrent_tools.py

[Copilot]

Pull request overview

This PR updates streaming response parsing so a single engine chunk can emit multiple ordered deltas, addressing concurrent tool-call streaming where reasoning/content/tool-call segments could previously remain buffered.

Changes:

• Changes ResponseParser.stream_chunk to return a list of parsed deltas and updates OpenAI/Anthropic streaming consumers.
• Updates GPT-OSS Harmony and default parser behavior for empty/no-op chunks under the new contract.
• Adjusts parser and endpoint tests to use the new list-return API and adds coverage for multi-delta ordering.

Reviewed changes

Copilot reviewed 13 out of 14 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
lmdeploy/serve/parsers/response_parser.py	Changes the base parser streaming contract and emits all parsed deltas from one chunk.
lmdeploy/serve/parsers/_openai_harmony.py	Wraps GPT-OSS Harmony streaming output in the new list-return format.
lmdeploy/serve/openai/api_server.py	Iterates over parsed deltas and attaches finish/logprob/token metadata to the last delta per engine chunk.
lmdeploy/serve/anthropic/streaming.py	Iterates over parsed deltas for Anthropic SSE streaming.
lmdeploy/version.py	Bumps version to 0.14.0a0.
tests/test_lmdeploy/serve/parsers/helpers.py	Adds a helper for tests that still assert first-delta behavior.
tests/test_lmdeploy/serve/parsers/test_qwen3_parser.py	Updates Qwen3 parser tests and adds direct multi-delta assertions.
tests/test_lmdeploy/serve/parsers/test_qwen3_5_parser.py	Updates Qwen3.5 parser tests for the list-return contract.
tests/test_lmdeploy/serve/parsers/test_llama3_parser.py	Updates Llama3 parser tests for the list-return contract.
tests/test_lmdeploy/serve/parsers/test_interns1_parser.py	Updates InternS1 parser tests for the list-return contract.
tests/test_lmdeploy/serve/parsers/test_gpt_oss_parser.py	Updates GPT-OSS parser tests for the list-return contract.
tests/test_lmdeploy/serve/parsers/test_glm47_parser.py	Updates GLM4.7 parser tests for the list-return contract.
tests/test_lmdeploy/serve/parsers/test_deepseek_v3_parser.py	Updates DeepSeek V3 parser tests for the list-return contract.
tests/test_lmdeploy/serve/anthropic/test_endpoints.py	Updates fake Anthropic parsers to return lists of deltas.

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[lvhan028]

cc @zhulinJulia24

[Copilot]

Pull request overview

Copilot reviewed 13 out of 14 changed files in this pull request and generated 1 comment.

[RunningLeon]

LGTM