[Frontend] Pythonic tool names flexibility (#14470)

[bjj]

This change remaps the tool names to func0..funcN during the parsing step so that pythonic tools only have to match a given regex rather than being strictly valid python. After parsing, the names are mapped back for the API return. This is useful because the OpenAI API is just JSON, and tool names are not really restricted to purely valid python function names.

The regex is then updated to accept leading underscores and kebab-case (the particular example that was plaguing me was n8n's wikipedia-api). Tests are added accordingly, and all pass.

FIX #14470

[github-actions]

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[bjj]

@mdepinet You might be the right person to comment on whether this is desirable, and if so if this is an acceptable approach