Implement cost and latency tracking

[ArtyomVancyan]

This pull request introduces a new metrics display feature to the node inspector panel in the web UI and refactors how inspection data is passed and rendered. The main changes include adding a dedicated Metrics component for latency, token, and cost metrics, updating the inspector panel to use this component, and cleaning up related props and styles for a more streamlined and visually consistent experience.

[Copilot]

Pull request overview

This PR adds end-to-end latency/token/cost metrics to the node inspector in the web UI by emitting metrics from the Python tracer stream and introducing a dedicated Metrics UI component, while also simplifying how inspector data is passed/rendered.

Changes:

• Add Formatter.metrics() and include metrics in streamed node_output messages.
• Add NodeMetrics typing + a new Metrics component and render it in InspectPanel.
• Add a helper script to (re)generate bundled model metadata (models.json) and remove the langsmith dependency.

Reviewed changes

Copilot reviewed 11 out of 13 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
scripts/models.py	New script to generate/update langgraphics/metadata/models.json from models.dev.
pyproject.toml	Removes langsmith from runtime deps.
langgraphics/streamer.py	Adds metrics to node_output payloads.
langgraphics/formatter.py	Replaces LangSmith utils usage; adds metrics extraction + latency/cost formatting.
langgraphics-web/src/types.ts	Adds NodeMetrics and metrics field on node output messages.
langgraphics-web/src/main.tsx	Passes nodeEntries into GraphCanvas (inspector now owned there).
langgraphics-web/src/index.css	Adds styles for the metrics chips/popovers.
langgraphics-web/src/components/Metrics.tsx	New UI component to display latency/tokens/cost.
langgraphics-web/src/components/InspectPanel.tsx	Renders Metrics when available; adds colorMode prop.
langgraphics-web/src/components/GraphCanvas.tsx	Owns InspectPanel and wires nodeEntries through.
README.md	Updates demo image sizing and refreshes the feature comparison table.

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[Copilot]

@ArtyomVancyan I've opened a new pull request, #11, to work on those changes. Once the pull request is ready, I'll request review from you.

[Copilot]

@ArtyomVancyan I've opened a new pull request, #12, to work on those changes. Once the pull request is ready, I'll request review from you.