Fix graph queue legacy LLM handling

[atobiszei]

This makes each requests create new LegacyServableExecutionContext.

[mzegla]

Would it make sense to wrap names in consts here?

[Copilot]

Pull request overview

This PR updates MediaPipe graph-queue handling for legacy HttpLLMCalculator graphs by introducing an execution-context side packet requirement and making OVMS_GRAPH_QUEUE_MAX_SIZE: AUTO resolve to a concrete, container-aware queue size.

Changes:

• Add LLM_NODE_EXECUTION_CONTEXTS side packet to generated/exported graphs and test graph templates/fixtures.
• Resolve graph-queue AUTO to min(restWorkers, getCoreCount) and disable graph queue when legacy HttpLLMCalculator graphs are missing the execution-context side packet.
• Adjust graph-queue related tests and wiring (including Bazel deps) to reflect the new behavior.

Reviewed changes

Copilot reviewed 17 out of 17 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/test/pull_hf_model_test.cpp	Updates expected graph content to include LLM_NODE_EXECUTION_CONTEXTS side packet.
src/test/mediapipeflow_test.cpp	Strengthens graph-queue AUTO and legacy-LLM compatibility coverage.
src/test/llm/visual_language_model/vlm_legacy_regular.pbtxt	Adds LLM_NODE_EXECUTION_CONTEXTS side packet for LLM node.
src/test/llm/visual_language_model/vlm_cb_regular.pbtxt	Adds LLM_NODE_EXECUTION_CONTEXTS side packet for LLM node.
src/test/llm/lm_legacy_regular.pbtxt	Adds LLM_NODE_EXECUTION_CONTEXTS side packet for LLM node.
src/test/llm/lm_cb_with_tool_parser.pbtxt	Adds LLM_NODE_EXECUTION_CONTEXTS side packet for LLM node.
src/test/llm/lm_cb_speculative.pbtxt	Adds LLM_NODE_EXECUTION_CONTEXTS side packet for LLM node.
src/test/llm/lm_cb_regular.pbtxt	Adds LLM_NODE_EXECUTION_CONTEXTS side packet for LLM node.
src/test/llm/lm_cb_prompt_lookup.pbtxt	Adds LLM_NODE_EXECUTION_CONTEXTS side packet for LLM node.
src/test/graph_export_test.cpp	Updates expected exported graph content to include execution-context side packet.
src/mediapipe_internal/mediapipegraphdefinition.hpp	Adds resolveAutoQueueSize() declaration.
src/mediapipe_internal/mediapipegraphdefinition.cpp	Implements AUTO queue-size resolution and disables queue for legacy LLM graphs missing execution context.
src/mediapipe_internal/mediapipegraphconfig.hpp	Simplifies queue-size storage to std::optional<int> and adds clearGraphQueueSize().
src/mediapipe_internal/graphqueue.cpp	Uses member sidePacketMaps consistently during graph helper initialization.
src/mediapipe_internal/BUILD	Adds dependency on //src:libovms_systeminfo for core-count based sizing.
src/graph_export/graph_export.cpp	Adds execution-context side packet to generated text-generation graph template.