docs: add clarity on use of custom packet type (#12) #76

Job	Run time
UI / Test	21s
Plugins / Lint (NLLB)	2m 5s
Skit / Lint (fmt + clippy)	3m 11s
UI / Lint (TypeScript + ESLint)	27s
Plugins / Lint (Sherpa-ONNX Plugins)	53s
E2E / Playwright E2E	7m 5s
UI / Build	27s
Plugins / Lint (Simple Plugins)	37s
Skit / Test	6m 17s
Plugins / Format Check	20s
Skit / Build	9m 12s
Plugins / Lint (Whisper)	35s
All Checks Passed	3s
	31m 33s

Provide feedback