[upstream #14701] #14701: Enforce the local parser size limit before uploading a Context document #252

Upstream PR: LibreChat-AI#14701, finding LibreChat-AI#14701 (comment)

When Context is routed through the local parser and fileConfig.documentParser.fileSizeLimit (default 15 MB) is below the endpoint upload limit, the client admits the file and uploads all of it before the server refuses with 413 PARSER_INPUT_LIMIT. The refusal is correct and shown to the user; the cost is the wasted upload.

Suggested fix: in client/src/utils/files.ts validation, apply the parser ceiling when the selected route is the local parser (not when a configured OCR or RAG text route will take the file), keeping the endpoint limit for those routes.