chore(ci): optimise runners, distribute test shards #8408

Job	Run time
Detect changes	8s
code-quality / code-quality	1m 31s
internal / 🧪 Unit Tests: Internal	6m 21s
typecheck / typecheck	2m 43s
e2e-webapp / 🧪 E2E Tests: Webapp	4m 15s
e2e / 🧪 CLI v3 tests (warp-windows-latest-x64-8x - npm)	4m 14s
e2e / 🧪 CLI v3 tests (warp-ubuntu-latest-x64-4x - pnpm)	1m 58s
webapp / 🧪 Unit Tests: Webapp (11, 12)	6m 32s
webapp / 🧪 Unit Tests: Webapp (5, 12)	8m 11s
webapp / 🧪 Unit Tests: Webapp (6, 12)	6m 20s
webapp / 🧪 Unit Tests: Webapp (4, 12)	5m 53s
webapp / 🧪 Unit Tests: Webapp (8, 12)	6m 44s
webapp / 🧪 Unit Tests: Webapp (10, 12)	6m 28s
e2e / 🧪 CLI v3 tests (warp-ubuntu-latest-x64-4x - npm)	1m 53s
webapp / 🧪 Unit Tests: Webapp (7, 12)	6m 26s
webapp / 🧪 Unit Tests: Webapp (1, 12)	6m 13s
e2e / 🧪 CLI v3 tests (warp-windows-latest-x64-8x - pnpm)	3m 55s
webapp / 🧪 Unit Tests: Webapp (9, 12)	6m 6s
webapp / 🧪 Unit Tests: Webapp (2, 12)	7m 8s
webapp / 🧪 Unit Tests: Webapp (3, 12)	6m 19s
webapp / 🧪 Unit Tests: Webapp (12, 12)	5m 59s
sdk-compat	-1s
packages	-1s
webapp / 📊 Merge Reports	26s
All PR Checks	5s
	1h 45m 46s

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