ui: Restructure repo to use tools/ui folder and ui / UI / llama-ui / LLAMA_UI naming (#23064)

* webui: Move static build output from `tools/server/public` to `build/ui` directory

* refactor: Move to `tools/ui`

* refactor: rename CMake variables and preprocessor defines

- Rename LLAMA_BUILD_WEBUI -> LLAMA_BUILD_UI (old kept as deprecated)
- Rename LLAMA_USE_PREBUILT_WEBUI -> LLAMA_USE_PREBUILT_UI (old kept as deprecated)
- Backward compat: old vars auto-forward to new ones with DEPRECATION warning
- Rename internal vars: WEBUI_SOURCE -> UI_SOURCE, WEBUI_SOURCE_DIR -> UI_SOURCE_DIR, etc.
- Rename HF bucket: LLAMA_WEBUI_HF_BUCKET -> LLAMA_UI_HF_BUCKET
- Emit both LLAMA_BUILD_WEBUI and LLAMA_BUILD_UI preprocessor defines
- Emit both LLAMA_WEBUI_DEFAULT_ENABLED and LLAMA_UI_DEFAULT_ENABLED

* refactor: rename CLI flags (--webui -> --ui) with backward compat

- Add --ui/--no-ui (old --webui/--no-webui kept as deprecated aliases)
- Add --ui-config (old --webui-config kept as deprecated alias)
- Add --ui-config-file (old --webui-config-file kept as deprecated alias)
- Add --ui-mcp-proxy/--no-ui-mcp-proxy (old --webui-mcp-proxy kept as deprecated)
- Add new env vars: LLAMA_ARG_UI, LLAMA_ARG_UI_CONFIG, LLAMA_ARG_UI_CONFIG_FILE, LLAMA_ARG_UI_MCP_PROXY
- C++ struct fields: params.ui, params.ui_config_json, params.ui_mcp_proxy added alongside old fields
- Backward compat: old fields synced to new ones in g_params_to_internals

* refactor: update C++ server internals with backward compat

- Rename json_webui_settings -> json_ui_settings (both kept in server_context_meta)
- Rename params.webui usage -> params.ui (both synced, old still works)
- JSON API emits both "ui"/"ui_settings" and "webui"/"webui_settings" keys
- Server routes use params.ui_mcp_proxy || params.webui_mcp_proxy
- Preprocessor guards use #if defined(LLAMA_BUILD_UI) || defined(LLAMA_BUILD_WEBUI)

* refactor: rename CI/CD workflows, artifacts, and build script

- Rename webui-build.yml -> ui-build.yml; artifact webui-build -> ui-build
- Rename webui-publish.yml -> ui-publish.yml; var HF_BUCKET_WEBUI_STATIC_OUTPUT -> HF_BUCKET_UI_STATIC_OUTPUT
- Rename server-webui.yml -> server-ui.yml; job webui-build/checks -> ui-build/checks
- Update server.yml: job/artifact refs webui-build -> ui-build
- Update release.yml: all webui-build/publish refs -> ui-build/publish; HF_TOKEN_WEBUI_STATIC_OUTPUT -> HF_TOKEN_UI_STATIC_OUTPUT
- Update server-self-hosted.yml: webui-build -> ui-build
- Update build-self-hosted.yml: HF_WEBUI_VERSION -> HF_UI_VERSION
- Rename webui-download.cmake -> ui-download.cmake (internal refs updated)
- Update labeler.yml: server/webui -> server/ui path label

* docs: update CODEOWNERS and server README docs

- Update CODEOWNERS: team ggml-org/llama-webui -> ggml-org/llama-ui, path /tools/server/webui/ -> /tools/ui/
- Update server README.md: CLI tables show --ui flags with deprecated --webui aliases
- Update server README-dev.md: "WebUI" -> "UI", paths updated to tools/ui/

* fix: Small fixes for UI build

* fix: CMake.txt syntax

* chore: Formatting

* fix: `.editorconfig` for llama-ui

* chore: Formatting

* refactor: Use `APP_NAME` in Error route

* refactor: Cleanup

* refactor: Single migration service

* make llama-ui a linkable target

* fix: UI Build output

* fix: Missing change

* fix: separate llama-ui npm build output into build/tools/ui/dist subfolder + use cmake npm build instead of downloading ui-build.yml artifacts in CI

* refactor: UI workflows cleanup

---------

Co-authored-by: Xuan Son Nguyen <son@huggingface.co>

tools/ui/src/lib/components/app/dialogs/DialogChatError.svelte

@@ -0,0 +1,80 @@
+<script lang="ts">
+	import * as AlertDialog from '$lib/components/ui/alert-dialog';
+	import { AlertTriangle, TimerOff } from '@lucide/svelte';
+	import { ErrorDialogType } from '$lib/enums';
+
+	interface Props {
+		open: boolean;
+		type: ErrorDialogType;
+		message: string;
+		contextInfo?: { n_prompt_tokens: number; n_ctx: number };
+		onOpenChange?: (open: boolean) => void;
+	}
+
+	let { open = $bindable(), type, message, contextInfo, onOpenChange }: Props = $props();
+
+	const isTimeout = $derived(type === ErrorDialogType.TIMEOUT);
+	const title = $derived(isTimeout ? 'TCP Timeout' : 'Server Error');
+	const description = $derived(
+		isTimeout
+			? 'The request did not receive a response from the server before timing out.'
+			: 'The server responded with an error message. Review the details below.'
+	);
+	const iconClass = $derived(isTimeout ? 'text-destructive' : 'text-amber-500');
+	const badgeClass = $derived(
+		isTimeout
+			? 'border-destructive/40 bg-destructive/10 text-destructive'
+			: 'border-amber-500/40 bg-amber-500/10 text-amber-600 dark:text-amber-400'
+	);
+
+	function handleOpenChange(newOpen: boolean) {
+		open = newOpen;
+		onOpenChange?.(newOpen);
+	}
+</script>
+
+<AlertDialog.Root {open} onOpenChange={handleOpenChange}>
+	<AlertDialog.Content>
+		<AlertDialog.Header>
+			<AlertDialog.Title class="flex items-center gap-2">
+				{#if isTimeout}
+					<TimerOff class={`h-5 w-5 ${iconClass}`} />
+				{:else}
+					<AlertTriangle class={`h-5 w-5 ${iconClass}`} />
+				{/if}
+
+				{title}
+			</AlertDialog.Title>
+
+			<AlertDialog.Description>
+				{description}
+			</AlertDialog.Description>
+		</AlertDialog.Header>
+
+		<div class={`rounded-lg border px-4 py-3 text-sm ${badgeClass}`}>
+			<p class="font-medium">{message}</p>
+
+			{#if contextInfo}
+				<div class="mt-2 space-y-1 text-xs opacity-80">
+					<p>
+						<span class="font-medium">Prompt tokens:</span>
+
+						{contextInfo.n_prompt_tokens.toLocaleString()}
+					</p>
+
+					{#if contextInfo.n_ctx}
+						<p>
+							<span class="font-medium">Context size:</span>
+
+							{contextInfo.n_ctx.toLocaleString()}
+						</p>
+					{/if}
+				</div>
+			{/if}
+		</div>
+
+		<AlertDialog.Footer>
+			<AlertDialog.Action onclick={() => handleOpenChange(false)}>Close</AlertDialog.Action>
+		</AlertDialog.Footer>
+	</AlertDialog.Content>
+</AlertDialog.Root>