feat: add Grafana Faro RUM, fix dashboards, add Grafana to admin nav

- Add @grafana/faro-web-sdk to UI; wire initializeFaro in hooks.client.ts
  gated on PUBLIC_FARO_COLLECTOR_URL (no-op in dev)
- Add Grafana Alloy service (faro.receiver) to homelab compose;
  Faro endpoint → alloy:12347 (faro.libnovel.cc via cloudflared)
- Add PUBLIC_FARO_COLLECTOR_URL env var to docker-compose.yml UI service
- Add Web Vitals dashboard (web-vitals.json): LCP/INP/CLS/TTFB/FCP p75
  stats + LCP/TTFB time-series + Faro exception logs from Loki
- Fix runner.json: strip libnovel_ prefix from all metric names
- Fix backend.json: replace 5 dead http_client_* panels with
  spanmetrics-based equivalents (Request Rate by Span Name + Latency
  by Span Name p95)
- Fix OTel collector: add service.telemetry.metrics.address: 0.0.0.0:8888
  so Prometheus can scrape collector self-metrics
- Add Grafana link to admin nav external tools; add admin_nav_grafana
  message key to all 5 locale files; recompile paraglide

ui/src/hooks.client.ts

@@ -1,5 +1,6 @@
 import * as Sentry from '@sentry/sveltekit';
 import { env } from '$env/dynamic/public';
+import { initializeFaro, getWebInstrumentations } from '@grafana/faro-web-sdk';
 
 // Sentry / GlitchTip client-side error tracking.
 // No-op when PUBLIC_GLITCHTIP_DSN is unset (e.g. local dev).
@@ -13,4 +14,21 @@ if (env.PUBLIC_GLITCHTIP_DSN) {
 	});
 }
 
+// Grafana Faro RUM — browser performance monitoring (Web Vitals, traces, errors).
+// No-op when PUBLIC_FARO_COLLECTOR_URL is unset (e.g. local dev).
+if (env.PUBLIC_FARO_COLLECTOR_URL) {
+	initializeFaro({
+		url: env.PUBLIC_FARO_COLLECTOR_URL,
+		app: {
+			name: 'libnovel-ui',
+			version: env.PUBLIC_BUILD_VERSION || 'dev',
+			environment: 'production'
+		},
+		instrumentations: [
+			// Core Web Vitals (LCP, CLS, INP, TTFB, FCP) + JS errors + console
+			...getWebInstrumentations({ captureConsole: false })
+		]
+	});
+}
+
 export const handleError = Sentry.handleErrorWithSentry();

ui/src/lib/paraglide/messages/_index.js

@@ -381,6 +381,7 @@ export * from './admin_nav_logs.js'
 export * from './admin_nav_uptime.js'
 export * from './admin_nav_push.js'
 export * from './admin_nav_gitea.js'
+export * from './admin_nav_grafana.js'
 export * from './admin_scrape_status_idle.js'
 export * from './admin_scrape_full_catalogue.js'
 export * from './admin_scrape_single_book.js'

ui/src/lib/paraglide/messages/admin_nav_grafana.js

@@ -0,0 +1,44 @@
+/* eslint-disable */
+import { getLocale, experimentalStaticLocale } from '../runtime.js';
+
+/** @typedef {import('../runtime.js').LocalizedString} LocalizedString */
+
+/** @typedef {{}} Admin_Nav_GrafanaInputs */
+
+const en_admin_nav_grafana = /** @type {(inputs: Admin_Nav_GrafanaInputs) => LocalizedString} */ () => {
+	return /** @type {LocalizedString} */ (`Grafana`)
+};
+
+const ru_admin_nav_grafana = /** @type {(inputs: Admin_Nav_GrafanaInputs) => LocalizedString} */ () => {
+	return /** @type {LocalizedString} */ (`Grafana`)
+};
+
+const id_admin_nav_grafana = /** @type {(inputs: Admin_Nav_GrafanaInputs) => LocalizedString} */ () => {
+	return /** @type {LocalizedString} */ (`Grafana`)
+};
+
+const pt_admin_nav_grafana = /** @type {(inputs: Admin_Nav_GrafanaInputs) => LocalizedString} */ () => {
+	return /** @type {LocalizedString} */ (`Grafana`)
+};
+
+const fr_admin_nav_grafana = /** @type {(inputs: Admin_Nav_GrafanaInputs) => LocalizedString} */ () => {
+	return /** @type {LocalizedString} */ (`Grafana`)
+};
+
+/**
+* | output |
+* | --- |
+* | "Grafana" |
+*
+* @param {Admin_Nav_GrafanaInputs} inputs
+* @param {{ locale?: "en" | "ru" | "id" | "pt" | "fr" }} options
+* @returns {LocalizedString}
+*/
+export const admin_nav_grafana = /** @type {((inputs?: Admin_Nav_GrafanaInputs, options?: { locale?: "en" | "ru" | "id" | "pt" | "fr" }) => LocalizedString) & import('../runtime.js').MessageMetadata<Admin_Nav_GrafanaInputs, { locale?: "en" | "ru" | "id" | "pt" | "fr" }, {}>} */ ((inputs = {}, options = {}) => {
+	const locale = experimentalStaticLocale ?? options.locale ?? getLocale()
+	if (locale === "en") return en_admin_nav_grafana(inputs)
+	if (locale === "ru") return ru_admin_nav_grafana(inputs)
+	if (locale === "id") return id_admin_nav_grafana(inputs)
+	if (locale === "pt") return pt_admin_nav_grafana(inputs)
+	return fr_admin_nav_grafana(inputs)
+});

ui/src/routes/admin/+layout.svelte

@@ -19,6 +19,7 @@
 		{ href: 'https://logs.libnovel.cc', label: () => m.admin_nav_logs() },
 		{ href: 'https://uptime.libnovel.cc', label: () => m.admin_nav_uptime() },
 		{ href: 'https://push.libnovel.cc', label: () => m.admin_nav_push() },
+		{ href: 'https://grafana.libnovel.cc', label: () => m.admin_nav_grafana() },
 		{ href: 'https://gitea.kalekber.cc/kamil/libnovel', label: () => m.admin_nav_gitea() }
 	];