fix(frontend): theme the surfaces that stayed light in dark mode - #10295

The base and head of this comparison were measured with different runner settings, so their benchmark values are not directly comparable.

What changed between base and head:

• CodSpeed runner v5 changed how benchmarks are measured (base 5.0.2 → head 4.19.1). View release notes
• Cycle estimation (on → off) changes how benchmark performance is calculated. Learn more about cycle estimation

Re-run the base with the same settings to get a valid performance comparison.

_{Comparing dark-theme-completion-infp-46 (5f755ab) with stable (0cb07cb)¹}