Improve UX with merged run view, method badges, grouped encounters, and mobile nav

Merges the run dashboard into the encounters page as a unified view at /runs/:runId,
adds encounter method grouping in the modal and badges on route rows, improves the
home page with recent runs, adds mobile hamburger nav, and polishes empty states.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/pages/index.ts

@@ -1,5 +1,4 @@
 export { Home } from './Home'
 export { NewRun } from './NewRun'
 export { RunList } from './RunList'
-export { RunDashboard } from './RunDashboard'
 export { RunEncounters } from './RunEncounters'