fix(webapp): prevent dashboard crash when span accessory text is not a string #5406

Job	Run time
sdk-compat / Cloudflare Workers	2m 7s
sdk-compat / Bun Runtime	2m 0s
e2e / 🧪 CLI v3 tests (ubuntu-latest - pnpm)	1m 48s
typecheck / typecheck	6m 30s
e2e / 🧪 CLI v3 tests (windows-latest - pnpm)	4m 6s
sdk-compat / Node.js 20.20 (ubuntu-latest)	1m 58s
sdk-compat / Deno Runtime	2m 2s
e2e / 🧪 CLI v3 tests (windows-latest - npm)	5m 37s
e2e / 🧪 CLI v3 tests (ubuntu-latest - npm)	1m 52s
units / packages / 🧪 Unit Tests: Packages (1, 1)	8m 41s
sdk-compat / Node.js 22.12 (ubuntu-latest)	1m 53s
units / webapp / 🧪 Unit Tests: Webapp (2, 8)	5m 33s
units / webapp / 🧪 Unit Tests: Webapp (4, 8)	7m 29s
units / webapp / 🧪 Unit Tests: Webapp (7, 8)	5m 55s
units / internal / 🧪 Unit Tests: Internal (3, 8)	8m 40s
units / webapp / 🧪 Unit Tests: Webapp (6, 8)	7m 57s
units / webapp / 🧪 Unit Tests: Webapp (5, 8)	4m 45s
units / webapp / 🧪 Unit Tests: Webapp (3, 8)	3m 10s
units / internal / 🧪 Unit Tests: Internal (2, 8)	7m 51s
units / internal / 🧪 Unit Tests: Internal (4, 8)	6m 3s
units / internal / 🧪 Unit Tests: Internal (7, 8)	5m 26s
units / internal / 🧪 Unit Tests: Internal (8, 8)	2m 30s
units / webapp / 🧪 Unit Tests: Webapp (8, 8)	2m 51s
units / internal / 🧪 Unit Tests: Internal (6, 8)	6m 32s
units / internal / 🧪 Unit Tests: Internal (5, 8)	6m 27s
units / webapp / 🧪 Unit Tests: Webapp (1, 8)	6m 4s
units / internal / 🧪 Unit Tests: Internal (1, 8)	7m 51s
units / webapp / 📊 Merge Reports	1s
units / internal / 📊 Merge Reports	1s
units / packages / 📊 Merge Reports	1s
	2h 13m 41s

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