webui: add setting for first-line chat titles (#21797)

* webui: add setting for first-line chat titles

Add an opt-in setting (`titleGenerationUseFirstLine`) to use the first
non-empty line of a prompt as the generated conversation title.

Previously, the complete multi-line prompt was being used, which created
long titles for complex queries. Coupled with
"Ask for confirmation before changing conversation title", the dialog
would overflow.

* Update tools/server/webui/src/lib/utils/text.ts

Co-authored-by: Aleksander Grygier <aleksander.grygier@gmail.com>

* Update tools/server/webui/src/lib/utils/text.ts

Co-authored-by: Aleksander Grygier <aleksander.grygier@gmail.com>

* webui: Run build to update the bundle

As requested in:
https://github.com/ggml-org/llama.cpp/pull/21797#pullrequestreview-4094935065

* webui: Fix missing import for NEWLINE_SEPARATOR

---------

Co-authored-by: Aleksander Grygier <aleksander.grygier@gmail.com>

tools/server/webui/src/lib/constants/settings-keys.ts

@@ -15,6 +15,7 @@ export const SETTINGS_KEYS = {
 	ENABLE_CONTINUE_GENERATION: 'enableContinueGeneration',
 	PDF_AS_IMAGE: 'pdfAsImage',
 	ASK_FOR_TITLE_CONFIRMATION: 'askForTitleConfirmation',
+	TITLE_GENERATION_USE_FIRST_LINE: 'titleGenerationUseFirstLine',
 	// Display
 	SHOW_MESSAGE_STATS: 'showMessageStats',
 	SHOW_THOUGHT_IN_PROGRESS: 'showThoughtInProgress',