Refresh the Flutter snapshot: v3 tickets V3-04 through V3-16, plus a fresh installable APK

V3-04 through V3-07, V3-10, V3-16 shipped complete; V3-11/V3-12/V3-14 shipped code-complete pending device/account verification; V3-08/V3-09 deferred behind a new V3-17 (self-hosted OSRM investigation). 316 tests passing, up from 221.

The APK is a fresh release build (debug-signed, no release signing config exists yet) with two build fixes applied: core library desugaring enabled for flutter_local_notifications, and sentry_flutter bumped to 9.27.0 (8.14.2's bundled Kotlin plugin was incompatible with this project's Kotlin 2.4.0 toolchain).

rippr-flutter-src/docs/v3/V3-08-road-routing.md

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+# V3-08 — Road-snapped routing and ETA
+
+**Phase** Route planning · **Depends on** V3-07, benefits from V3-01, **blocked on V3-17**
+· **Size** L · **Status** Deferred
+
+## Goal
+Resolve the actual shortest path along roads between pins, and estimate how long the ride
+will take.
+
+## Context
+This is what Dylan asked for. It is also the ticket with a **decision that cannot be
+deferred**: road-snapped routing needs a routing engine over OpenStreetMap data, and the
+choice has ongoing consequences.
+
+**Decided, not deferred:** self-hosted OSRM (see the table below). What's actually
+deferred is standing one up — that's [V3-17](V3-17-osrm-hosting.md), split out on
+request because provisioning a server is a different kind of work from building the app
+code that calls it, and this ticket cannot start until V3-17 has something to point
+`RoutingService` at.
+
+## Design
+
+### Choosing an engine — decide before writing code
+
+| Option | Trade-off |
+|---|---|
+| **Public OSRM demo** | Free, zero setup, **explicitly not for production**, rate-limited. Prototype only. |
+| **Self-hosted OSRM** | Fast, well understood. Needs a machine and a regional OSM extract (a province is a few GB). |
+| **GraphHopper** | Self-hostable, good cycling/motorcycle profiles, friendlier ETAs |
+| **Valhalla** | Best multi-modal profiles, heaviest to run |
+| **Mapbox / Google** | No ops, per-request billing, an API key shipped in the app |
+
+**Profiles matter more here than usual.** A motorcycle route and a bicycle route between
+the same pins genuinely differ — cycling engines avoid motorways, and a motorcyclist often
+wants the twisty road rather than the fast one. This is where V3-01 pays off: the activity
+selects the profile.
+
+Put it behind a `RoutingService` interface with a fake, exactly as `LocationSource` did for
+GPS. That seam is what made swapping the location engine cheap, and the same argument
+applies here.
+
+### ETA is a promise, and easy to get wrong
+Engines estimate from posted speed limits. That is not how long *you* take. Once there is
+history, the rider's own average moving speed for that activity — already stored on every
+`Trip` — is a better predictor.
+
+Show the engine's estimate, then replace it with a personal one once there is enough
+history to justify it. Label which is which.
+
+### Caching
+Cache the returned polyline on `Route.geometry`. A saved plan must open offline and must
+not re-bill a request every time it is viewed.
+
+## Implementation
+1. Decide the engine. Write the decision and its reasoning into this file.
+2. `RoutingService` interface + implementation + `FakeRoutingService`
+3. Resolve on pin change, debounced — not on every drag frame
+4. Persist geometry, distance and duration on `Route`
+5. Personal ETA from `Trip` history, once ≥5 rides of that activity exist
+6. Graceful offline behaviour: fall back to straight lines and say so
+
+## Acceptance criteria
+- [ ] Pins resolve to a road-following polyline
+- [ ] Distance reflects the road path, not the straight line
+- [ ] Activity changes the profile and can change the route
+- [ ] A saved route renders offline from cached geometry, with no network call
+- [ ] Offline with no cache degrades to straight lines with a visible explanation
+- [ ] No API key is committed to the repository
+
+## Tests
+- `FakeRoutingService` drives every path: success, failure, offline, empty
+- Cached geometry means no second request — assert the fake is called once
+- Personal ETA maths against fixed history
+- **No live network calls in any test**
+
+## Risks
+- **Vendor lock-in and cost.** The interface is the mitigation.
+- Debouncing matters: dragging a pin could otherwise fire dozens of requests.
+- OSM route quality varies. It will occasionally suggest something daft; that is the data,
+  not a bug to chase.
+
+## Out of scope
+Turn-by-turn navigation and voice guidance. That is a different product.