Improve devtools chart signals

[SandroMaglione]

Summary

• Replace framework transition text with compact semantic badges while preserving complete accessible labels.
• Keep ELK label measurements aligned with icon-only and corner-badge presentations.
• Improve chart contrast and colorblind readability, with explicit red styling for failure routes and errors.

Changeset

• Added or updated for a library or package-metadata change
• Not required because this PR does not change a publishable package

Validation

• pnpm check
• Automated type-performance measurement passed or was not required
• Automated runtime- and memory-performance measurement passed or was not required

The change is limited to the devtools browser chart and does not affect the public TypeScript API or core runtime. The required local pnpm perf:runtime smoke test also completed successfully.