[DERCBOT-1791] Expose full footnote metadata and title fallback flag

[scezen]

Ticket : DERCBOT-1791

Goal

Let the front-end reliably hide footnotes with fallback titles without relying on hardcoded strings, while still exposing full document metadata for future filtering needs.

Details

• Added isTitleFallback to RAG footnotes and propagated it from the orchestrator to the bot engine and web connector (camelCase on the client side via snake_case mapping).
• Exposed full metadata on footnotes so the front-end can filter using any ingested field (including is_title_fallback).
• Aligned the server-side mapping to read is_title_fallback from document metadata and include it in the footnote payload.

Note :

• We keep the existing response structure and only add optional fields (backward compatible).
• metadata keeps original keys from ingestion (often snake_case), while isTitleFallback is a typed convenience field.

[assouktim]

I think you can remove the is_title_fallback attribute, everything is in the metadata. Use it from there.

[scezen]

I think you can remove the is_title_fallback attribute, everything is in the metadata. Use it from there.

Yep, not a mistake I kept the same idea as 'title', which is also in metadata but still exposed as a first‑class field so the front-end has a clear and stable boolean to use. The metadata map is free-form and its keys can change so I tried something a bit more safe.

But I will ajust it ASAP.

[assouktim]

Thanks!