Remove direct public OSRM routing from Mobile

[stef-k]

Summary

• remove direct public OSRM routing, its HTTP client, provider-specific parsing/retry behavior, and obsolete route cache
• preserve valid downloaded Segment geometry and use explicit local Direct guidance otherwise
• add bounded schema-9 cleanup for only the legacy cached_osrm_route preference
• make Direct progress, arrival, announcements, replacement, and stop lifecycle independent of a loaded Trip graph
• retain authentication, synchronization, downloaded Trip data, and the interactive OSM live tile cache

Closes #259
Parent epic: #253
Coordinated release: stef-k/Wayfarer#505

Validation

• focused navigation, geometry, lifecycle, and decommission selections passed
• complete Release suite: 1,897 passed, 0 failed, 0 skipped
• Release test/Core build passed
• Android Release build passed with retained dependency warnings only
• Agent Code Guard completed with REVIEW and no FAIL or INCOMPLETE
• git diff --check 421cd736...HEAD passed

Database / migration notes

• advances the installed mobile schema to version 9
• removes only the obsolete cached_osrm_route preference
• cleanup is bounded and idempotent
• no downloaded Trip, Segment geometry, Timeline, synchronization, authentication, queue, or live-tile data is removed

UI evidence

No screenshots are required: the change removes a provider path and retains the existing navigation presentation. Direct guidance is now explicitly classified and its lifecycle is covered at the production service seams.

Release boundary

This PR does not implement authenticated Wayfarer routing (#260) or retained-route persistence (#261). After merge, Mobile supports valid saved Segment geometry or local Direct guidance with no direct routing-provider contact.

[github-actions]

Package	Line Rate	Branch Rate	Complexity	Health
WayfarerMobile.Core	88%	80%	994	✔
Summary	88% (1389 / 1585)	80% (689 / 866)	994	✔