fix(core): drop unique-symbol brand on LocalsKey to fix dual-package builds #6155

Job	Run time
Detect changes	3s
typecheck / typecheck	7m 31s
sdk-compat / Node.js 22.12 (ubuntu-latest)	2m 5s
sdk-compat / Bun Runtime	2m 21s
e2e-webapp / 🧪 E2E Tests: Webapp	4m 13s
sdk-compat / Cloudflare Workers	2m 26s
sdk-compat / Node.js 20.20 (ubuntu-latest)	2m 10s
e2e / 🧪 CLI v3 tests (windows-latest - npm)	4m 31s
e2e / 🧪 CLI v3 tests (ubuntu-latest - npm)	1m 49s
e2e / 🧪 CLI v3 tests (windows-latest - pnpm)	4m 48s
webapp / 🧪 Unit Tests: Webapp (1, 8)	6m 3s
sdk-compat / Deno Runtime	2m 8s
webapp / 🧪 Unit Tests: Webapp (3, 8)	3m 58s
packages / 🧪 Unit Tests: Packages (1, 1)	9m 9s
webapp / 🧪 Unit Tests: Webapp (8, 8)	6m 8s
webapp / 🧪 Unit Tests: Webapp (4, 8)	6m 38s
e2e / 🧪 CLI v3 tests (ubuntu-latest - pnpm)	2m 2s
webapp / 🧪 Unit Tests: Webapp (7, 8)	4m 5s
webapp / 🧪 Unit Tests: Webapp (6, 8)	8m 41s
webapp / 🧪 Unit Tests: Webapp (5, 8)	6m 39s
webapp / 🧪 Unit Tests: Webapp (2, 8)	3m 59s
internal / 🧪 Unit Tests: Internal (7, 8)	6m 45s
internal / 🧪 Unit Tests: Internal (8, 8)	2m 49s
internal / 🧪 Unit Tests: Internal (3, 8)	8m 57s
internal / 🧪 Unit Tests: Internal (4, 8)	6m 30s
internal / 🧪 Unit Tests: Internal (2, 8)	13m 2s
internal / 🧪 Unit Tests: Internal (5, 8)	6m 28s
internal / 🧪 Unit Tests: Internal (1, 8)	6m 30s
internal / 🧪 Unit Tests: Internal (6, 8)	6m 39s
webapp / 📊 Merge Reports	47s
packages / 📊 Merge Reports	24s
internal / 📊 Merge Reports	30s
All PR Checks	4s
	2h 30m 52s

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