[@W-21514384] fix(api-summary): resolve gRPC navigation when clicking nested span badges

[alexpmule]

Summary

Fixes gRPC method badge clicks not triggering navigation in the API summary TOC.

• Root cause: _navigateItem was reading e.composedPath()[0] (the deepest element clicked). For gRPC methods, the <a> contains a child <span class="grpc-stream-type">, so clicking the badge returned the span — which has no data-id — and the handler silently exited.
• Fix: Walk composedPath() until finding the first element with both data-id and data-shape-type, instead of assuming the first element always has them.
• REST method navigation is unaffected (anchor is still the first element with dataset for REST).

Changes

• src/ApiSummary.js — _navigateItem: walk composedPath to find data-bearing ancestor
• test/api-summary.test.js — 2 new regression tests in the gRPC suite:
  • Click on .grpc-stream-type span → event fires with correct id and type: "method"
  • Click directly on .method-label.grpc-container anchor → still works
• package.json — version bump 4.6.18 → 4.6.19

Test plan

• npm test passes (125 tests, 0 failures, 95.62% coverage)
• New test: clicking gRPC span badge fires api-navigation-selection-changed
• New test: clicking gRPC anchor directly still fires the event
• Manual: load a gRPC API in the demo, click Unary/Bidirectional badges → navigates to method docs
• Manual: REST method badges still navigate correctly

Test in API Console

Screen.Recording.2026-03-10.at.2.45.29.PM.mov

GUS

W-21514384