docs(vscode-lm): clarify VS Code LM API integration warning

[hannesrudolph]

This PR now updates the correct warning in the settings UI:

• Replaced experimental warning in webview UI: webview-ui/src/i18n/locales/en/settings.json
• Reverted unintended change to extension package description key: src/package.nls.json

New warning text:
"Note: Models accessed via the VS Code Language Model API may be wrapped or fine-tuned by the provider, so behavior can differ from using the same model directly from a typical provider or router. To use a model from the Language Model dropdown, first switch to that model and then click Accept in the Copilot Chat prompt; otherwise you may see an error such as 400 "The requested model is not supported"."

[Copilot]

Pull Request Overview

This PR clarifies the VS Code Language Model API integration warning to help users better understand potential model behavior differences and avoid common errors.

• Updates the description to use "provider" terminology instead of "vendor"
• Adds warning about potential behavior differences when models are wrapped or fine-tuned
• Provides specific instructions for proper model selection to avoid 400 errors

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_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

[roomote]

I found some minor improvements worth addressing to improve consistency and settings UI rendering.

[roomote]

I found some issues that need attention. Notably, a non-breaking hyphen is used in one updated string which can render inconsistently; recommend standard hyphen for consistency with the webview copy.

[roomote]

I found one minor readability improvement for the settings copy; see inline suggestion.

[roomote]

I found a localization regression: non-English locale files replaced localized copy with English. Recommend restoring localized strings in those files and limiting this change to the English locale, or follow up with proper translations. No other new issues found.

[roomote]

P2: Localization regression — this replaces the previous German translation with English. Please keep the localized copy or provide a German translation to avoid degrading i18n completeness here and across other locales changed in this PR.

Suggested change

"vscodeLmWarning": "Note: Models accessed via the VS Code Language Model API may be wrapped or fine-tuned by the provider, so behavior can differ from using the same model directly from a typical provider or router. To use a model from the Language Model dropdown, first switch to that model and then click Accept in the Copilot Chat prompt; otherwise you may see an error such as 400 \"The requested model is not supported\".",

"vscodeLmWarning": "Hinweis: Dies ist eine sehr experimentelle Integration und die Anbieterunterstützung variiert. Wenn Sie einen Fehler über ein nicht unterstütztes Modell erhalten, liegt das Problem auf Anbieterseite.",

[roomote]

P2: Localization regression — this replaces the previous Chinese translation with English. Please restore the localized string or provide a Chinese translation.

Suggested change

"vscodeLmWarning": "Note: Models accessed via the VS Code Language Model API may be wrapped or fine-tuned by the provider, so behavior can differ from using the same model directly from a typical provider or router. To use a model from the Language Model dropdown, first switch to that model and then click Accept in the Copilot Chat prompt; otherwise you may see an error such as 400 \"The requested model is not supported\".",

"vscodeLmWarning": "注意：这是一个非常实验性的集成，提供商支持会有所不同。如果您收到有关不支持模型的错误，则这是提供商方面的问题。",

[roomote]

I found some issues that need attention related to localization. The updated English warning text was copied into non-English locale files, replacing existing translations. This creates inconsistent UI and regresses i18n. Please keep the change in en only and either restore previous translations or mark them for translation.

[roomote]

[P2] The English warning text replaces the Spanish translation in this locale. Recommend reverting this line here (and in other non-English locales) to the previous localized copy and updating only en; track translation updates separately to avoid regressing i18n.

[roomote]

I found some issues that need attention: the warning references a specific provider UI (Copilot Chat). This panel is provider-agnostic for the VS Code LM API, so referencing Copilot directly may confuse users of other providers. Recommend wording that generalizes the acceptance step while keeping Copilot as an example.

[roomote]

[P2] Generalize provider-specific instruction: This warning references “Copilot Chat”, but the VS Code LM API can be provided by other extensions. Consider replacing 'click Accept in the Copilot Chat prompt' with 'click Accept in your provider's prompt (e.g., Copilot Chat)' to avoid provider-specific wording.