feat(sdk): browser-side chat client + transport (3/5) #5834

Job	Run time
sdk-compat / Deno Runtime	36s
typecheck / typecheck	43s
e2e / 🧪 CLI v3 tests (ubuntu-latest - pnpm)	20s
e2e / 🧪 CLI v3 tests (windows-latest - npm)	49s
sdk-compat / Cloudflare Workers	32s
sdk-compat / Bun Runtime	32s
e2e / 🧪 CLI v3 tests (ubuntu-latest - npm)	21s
e2e / 🧪 CLI v3 tests (windows-latest - pnpm)	49s
sdk-compat / Node.js 22.12 (ubuntu-latest)	42s
sdk-compat / Node.js 20.20 (ubuntu-latest)	32s
units / e2e-webapp / 🧪 E2E Tests: Webapp	1m 22s
units / packages / 🧪 Unit Tests: Packages (1, 1)	1m 0s
units / webapp / 🧪 Unit Tests: Webapp (1, 8)	1m 7s
units / webapp / 🧪 Unit Tests: Webapp (2, 8)	1m 4s
units / webapp / 🧪 Unit Tests: Webapp (5, 8)	54s
units / webapp / 🧪 Unit Tests: Webapp (4, 8)	1m 4s
units / webapp / 🧪 Unit Tests: Webapp (7, 8)	1m 6s
units / webapp / 🧪 Unit Tests: Webapp (6, 8)	59s
units / webapp / 🧪 Unit Tests: Webapp (3, 8)	1m 1s
units / webapp / 🧪 Unit Tests: Webapp (8, 8)	53s
units / internal / 🧪 Unit Tests: Internal (2, 8)	52s
units / internal / 🧪 Unit Tests: Internal (5, 8)	1m 5s
units / internal / 🧪 Unit Tests: Internal (1, 8)	52s
units / internal / 🧪 Unit Tests: Internal (7, 8)	51s
units / internal / 🧪 Unit Tests: Internal (4, 8)	1m 2s
units / internal / 🧪 Unit Tests: Internal (3, 8)	58s
units / internal / 🧪 Unit Tests: Internal (8, 8)	53s
units / internal / 🧪 Unit Tests: Internal (6, 8)	1m 4s
units / packages / 📊 Merge Reports	24s
units / internal / 📊 Merge Reports	23s
units / webapp / 📊 Merge Reports	21s
	25m 11s

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