webui : added download action (#13552)

[srogmann]

This PR adds a download action in Svelte, mirroring the implementation from the previous React release (see #13552).
The filename now includes a prefix derived from the beginning of the conversation text.

[mofosyne]

Looks reasonable. Matches PR description. Note that it outputs the conversation as JSON.

[srogmann]

There was a JSON-download in

llama.cpp/tools/server/webui/src/components/Header.tsx

Line 39 in b34c859

const downloadConversation = () => {

[allozaur]

Hey, @srogmann, thanks for this! I was thinking that maybe additional to this we could add importing/uploading conversations as well? Let me know if u would like to add this or rather have me take over this.

[srogmann]

Hi @allozaur , I thought about a transfer of master...srogmann:llama.cpp:feature/import_export_all to Svelte.

[srogmann]

I've added import and export functionality for all conversations. However, import currently only supports importing all conversations at once. Importing individual conversations is still missing (the import could detect if the JSON file contains just one conversation and then import only that one).

[allozaur]

Hey! I will take a closer look at these changes this week. I'll keep u posted 🙂