fix(sdk): preserve partial assistant message on chat stream failure #8777

Job	Run time
code-quality / code-quality	2m 18s
Detect changes	6s
e2e-webapp / 🧪 E2E Tests: Webapp	3m 37s
runops-guard / runops-guard	1m 57s
internal / 🧪 Unit Tests: Internal	5m 41s
packages / 🧪 Unit Tests: Packages (2, 3)	4m 3s
packages / 🧪 Unit Tests: Packages (3, 3)	5m 12s
packages / 🧪 Unit Tests: Packages (1, 3)	3m 23s
sdk-compat / Deno Runtime	2m 51s
sdk-compat / Bun Runtime	2m 40s
typecheck / typecheck	3m 44s
sdk-compat / Node.js 22.23 (warp-ubuntu-latest-x64-4x)	2m 16s
sdk-compat / Node.js 24.18 (warp-ubuntu-latest-x64-4x)	2m 17s
sdk-compat / Cloudflare Workers	2m 46s
webapp / 🧪 Unit Tests: Webapp (4, 12)	6m 6s
webapp / 🧪 Unit Tests: Webapp (5, 12)	6m 7s
sdk-compat / Node.js 26.4 (warp-ubuntu-latest-x64-4x)	2m 58s
webapp / 🧪 Unit Tests: Webapp (9, 12)	6m 8s
webapp / 🧪 Unit Tests: Webapp (11, 12)	6m 8s
webapp / 🧪 Unit Tests: Webapp (7, 12)	6m 7s
webapp / 🧪 Unit Tests: Webapp (1, 12)	6m 7s
webapp / 🧪 Unit Tests: Webapp (3, 12)	5m 46s
webapp / 🧪 Unit Tests: Webapp (8, 12)	6m 7s
webapp / 🧪 Unit Tests: Webapp (6, 12)	6m 6s
sdk-compat / Node.js 20.20 (warp-ubuntu-latest-x64-4x)	2m 36s
webapp / 🧪 Unit Tests: Webapp (10, 12)	6m 8s
webapp / 🧪 Unit Tests: Webapp (2, 12)	6m 5s
webapp / 🧪 Unit Tests: Webapp (12, 12)	6m 3s
e2e	0s
packages / 📊 Merge Reports	16s
All PR Checks	5s
webapp / 📊 Merge Reports	1s
	2h 1m 45s

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