refactor(analytics): centralize landing page Umami tracking via env vars

Replace hardcoded Umami website IDs in all 10 Astro landing pages with
import.meta.env.PUBLIC_UMAMI_WEBSITE_ID, following the same pattern
as the web apps.

- Add UMAMI_WEBSITE_ID_*_LANDING vars for all 10 landings in .env.development
- Add landing page configs to generate-env.mjs
- Replace hardcoded IDs with env var in 7 existing Layout.astro files
- Add Umami tracking to 3 missing landings (NutriPhi, Presi, Mukke)
- Fix Todo Landing invalid ID ("todo-landing" -> proper UUID)
- Update ANALYTICS.md with new landing page IDs

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/clock/apps/landing/src/layouts/Layout.astro

@@ -38,10 +38,15 @@ const {
 		/>
 
 		<!-- Umami Analytics -->
-		<script
-			defer
-			src="https://stats.mana.how/script.js"
-			data-website-id="0332b471-a022-46af-a726-0f45932bfd58"></script>
+		{
+			import.meta.env.PUBLIC_UMAMI_WEBSITE_ID && (
+				<script
+					defer
+					src="https://stats.mana.how/script.js"
+					data-website-id={import.meta.env.PUBLIC_UMAMI_WEBSITE_ID}
+				/>
+			)
+		}
 
 		<title>{title}</title>
 	</head>