fix(sdk): preserve partial assistant message on chat stream failure #8779

Job	Run time
Detect changes	6s
code-quality / code-quality	2m 10s
e2e-webapp / 🧪 E2E Tests: Webapp	3m 49s
packages / 🧪 Unit Tests: Packages (2, 3)	3m 29s
packages / 🧪 Unit Tests: Packages (1, 3)	3m 17s
internal / 🧪 Unit Tests: Internal	5m 5s
runops-guard / runops-guard	1m 30s
packages / 🧪 Unit Tests: Packages (3, 3)	4m 44s
typecheck / typecheck	2m 32s
sdk-compat / Deno Runtime	2m 49s
sdk-compat / Node.js 26.4 (warp-ubuntu-latest-x64-4x)	2m 39s
sdk-compat / Bun Runtime	2m 36s
sdk-compat / Node.js 24.18 (warp-ubuntu-latest-x64-4x)	2m 23s
sdk-compat / Node.js 20.20 (warp-ubuntu-latest-x64-4x)	1m 32s
sdk-compat / Node.js 22.23 (warp-ubuntu-latest-x64-4x)	2m 6s
sdk-compat / Cloudflare Workers	2m 38s
webapp / 🧪 Unit Tests: Webapp (4, 12)	4m 40s
webapp / 🧪 Unit Tests: Webapp (6, 12)	4m 41s
webapp / 🧪 Unit Tests: Webapp (2, 12)	4m 40s
webapp / 🧪 Unit Tests: Webapp (3, 12)	4m 39s
webapp / 🧪 Unit Tests: Webapp (5, 12)	4m 40s
webapp / 🧪 Unit Tests: Webapp (8, 12)	4m 44s
webapp / 🧪 Unit Tests: Webapp (1, 12)	4m 40s
webapp / 🧪 Unit Tests: Webapp (10, 12)	4m 39s
webapp / 🧪 Unit Tests: Webapp (11, 12)	4m 39s
webapp / 🧪 Unit Tests: Webapp (9, 12)	4m 39s
webapp / 🧪 Unit Tests: Webapp (7, 12)	4m 40s
e2e	0s
webapp / 🧪 Unit Tests: Webapp (12, 12)	4m 40s
packages / 📊 Merge Reports	12s
All PR Checks	5s
webapp / 📊 Merge Reports	1s
	1h 39m 44s

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