feature(webapp): Show a v3 deprecation notice in the side bar #4792

Job	Run time
sdk-compat / Bun Runtime	1m 51s
typecheck / typecheck	6m 8s
sdk-compat / Deno Runtime	1m 52s
e2e / 🧪 CLI v3 tests (windows-latest - npm)	4m 9s
e2e / 🧪 CLI v3 tests (ubuntu-latest - npm)	1m 48s
sdk-compat / Node.js 20.20 (ubuntu-latest)	1m 57s
e2e / 🧪 CLI v3 tests (ubuntu-latest - pnpm)	1m 51s
sdk-compat / Node.js 22.12 (ubuntu-latest)	2m 5s
e2e / 🧪 CLI v3 tests (windows-latest - pnpm)	3m 53s
units / packages / 🧪 Unit Tests: Packages (1, 1)	6m 32s
units / internal / 🧪 Unit Tests: Internal (2, 8)	6m 34s
units / webapp / 🧪 Unit Tests: Webapp (1, 8)	5m 44s
units / webapp / 🧪 Unit Tests: Webapp (6, 8)	3m 39s
units / internal / 🧪 Unit Tests: Internal (6, 8)	4m 51s
units / webapp / 🧪 Unit Tests: Webapp (2, 8)	3m 52s
units / webapp / 🧪 Unit Tests: Webapp (3, 8)	3m 9s
units / internal / 🧪 Unit Tests: Internal (8, 8)	3m 36s
units / internal / 🧪 Unit Tests: Internal (3, 8)	6m 20s
units / webapp / 🧪 Unit Tests: Webapp (4, 8)	5m 46s
units / webapp / 🧪 Unit Tests: Webapp (7, 8)	5m 49s
units / internal / 🧪 Unit Tests: Internal (1, 8)	5m 56s
units / webapp / 🧪 Unit Tests: Webapp (8, 8)	2m 28s
units / webapp / 🧪 Unit Tests: Webapp (5, 8)	6m 33s
units / internal / 🧪 Unit Tests: Internal (7, 8)	5m 16s
units / internal / 🧪 Unit Tests: Internal (5, 8)	4m 0s
sdk-compat / Cloudflare Workers	2m 6s
units / internal / 🧪 Unit Tests: Internal (4, 8)	5m 34s
units / packages / 📊 Merge Reports	1s
units / webapp / 📊 Merge Reports	1s
units / internal / 📊 Merge Reports	1s
	1h 53m 22s

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