Persist assistant conversations per session

[EvenSol]

Summary

• persist AI helper chat history in session state and include recent turns when forming prompts and offline fallbacks
• upgrade the what-if sidebar chat to retain structured history, feed it into result summaries, and reset inputs between turns
• document that both assistants remember conversation context across a session

Testing

• python -m compileall components services docs

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https://chatgpt.com/codex/tasks/task_e_68fc4aff8724832db2c12d97d0f72f4c

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Parse multiple components in natural language scenario prompts

The component matcher uses a greedy name capture ([A-Za-z0-9-\s]+), so the first match absorbs the rest of the prompt and no additional components are detected. For example, plan_scenario("90% methane and 10% ethane at 40 °C") only produces one match and normalizes to 100 % methane, ignoring the ethane specification. This makes the new natural-language setup silently produce the wrong fluid when users separate components with common phrases like “and”, which is a primary use case of the feature.

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