feature(webapp): Show a v3 deprecation notice in the side bar #4791

Job	Run time
sdk-compat / Deno Runtime	2m 0s
sdk-compat / Node.js 22.12 (ubuntu-latest)	1m 57s
sdk-compat / Cloudflare Workers	2m 9s
sdk-compat / Node.js 20.20 (ubuntu-latest)	1m 57s
sdk-compat / Bun Runtime	1m 50s
e2e / 🧪 CLI v3 tests (ubuntu-latest - pnpm)	1m 51s
e2e / 🧪 CLI v3 tests (windows-latest - pnpm)	3m 34s
units / packages / 🧪 Unit Tests: Packages (1, 1)	8m 7s
typecheck / typecheck	6m 6s
e2e / 🧪 CLI v3 tests (ubuntu-latest - npm)	1m 47s
e2e / 🧪 CLI v3 tests (windows-latest - npm)	3m 22s
units / webapp / 🧪 Unit Tests: Webapp (6, 8)	4m 14s
units / webapp / 🧪 Unit Tests: Webapp (8, 8)	2m 21s
units / webapp / 🧪 Unit Tests: Webapp (4, 8)	5m 48s
units / webapp / 🧪 Unit Tests: Webapp (5, 8)	7m 48s
units / webapp / 🧪 Unit Tests: Webapp (3, 8)	3m 4s
units / webapp / 🧪 Unit Tests: Webapp (1, 8)	5m 38s
units / internal / 🧪 Unit Tests: Internal (1, 8)	6m 40s
units / internal / 🧪 Unit Tests: Internal (4, 8)	5m 21s
units / internal / 🧪 Unit Tests: Internal (6, 8)	4m 45s
units / webapp / 🧪 Unit Tests: Webapp (2, 8)	3m 31s
units / webapp / 🧪 Unit Tests: Webapp (7, 8)	5m 45s
units / internal / 🧪 Unit Tests: Internal (5, 8)	3m 58s
units / internal / 🧪 Unit Tests: Internal (7, 8)	5m 32s
units / internal / 🧪 Unit Tests: Internal (3, 8)	6m 30s
units / internal / 🧪 Unit Tests: Internal (8, 8)	3m 14s
units / internal / 🧪 Unit Tests: Internal (2, 8)	10m 2s
units / webapp / 📊 Merge Reports	48s
units / packages / 📊 Merge Reports	22s
units / internal / 📊 Merge Reports	18s
	2h 0m 19s

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