Add E2E tests for waypoint notes and nearby POI snap; archive waypoint-notes

- E2E: type a note, blur, verify it persists and appears in GPX <desc> on <wpt>
- E2E: mock Overpass, select waypoint, verify Nearby list, snap to POI,
  verify note prefix prepended
- Sync waypoint-notes delta spec → openspec/specs/waypoint-notes/spec.md
- Archive waypoint-notes change

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

openspec/changes/waypoint-notes/proposal.md

@@ -1,76 +0,0 @@
-## Why
-
-Waypoints in the Planner are just coordinates with optional names. When planning
-a multi-day route, users need to note *why* a waypoint matters: "Water refill at
-gas station", "Tricky gravel crossing - dismount", "Campsite with shelter",
-"Scenic viewpoint over the valley". Without notes, this context lives outside the
-tool (paper, chat messages, memory) and gets lost.
-
-A related problem: waypoints placed by clicking on the map often miss nearby
-points of interest by a few meters. A user clicks near a water source, campsite,
-or shelter, but the waypoint lands on the road 30 meters away. They have to
-manually look up the POI name, type it in, and nudge the waypoint. This is
-tedious and error-prone, especially on mobile. POIs give immediate context to
-waypoints - the same kind of context that notes provide in free-form text.
-
-## What Changes
-
-- **Per-waypoint text notes**: Each waypoint in the Yjs document gets an optional
-  `note` string field. Plain text, no rich formatting.
-- **Inline editing in sidebar**: Click the note area under a waypoint name to
-  edit. Auto-saves on blur. Placeholder "Add a note..." when empty.
-- **Map indicator**: Markers with notes show a small note icon. Hover/tap reveals
-  the note in a tooltip.
-- **GPX export**: Notes are included as `<desc>` elements in waypoint GPX output.
-- **Shared type update**: The `Waypoint` interface in `@trails-cool/types` gets
-  an optional `note` field.
-- **Nearby POI display**: When a waypoint is selected, query nearby POIs from
-  OpenStreetMap (via Overpass API) and show them as small markers on the map and
-  as a list in the sidebar.
-- **Snap to POI**: Click a nearby POI to move the waypoint to its exact
-  coordinates, inheriting the POI's name and type as a note prefix (e.g.,
-  "⛺ Campsite - Waldcamp Fichtelberg"). The user can edit after snapping.
-
-## Capabilities
-
-### New Capabilities
-
-- `waypoint-notes`: Per-waypoint text notes with inline editing, map indicators,
-  and GPX export
-- `poi-snapping`: Nearby POI lookup via Overpass API with snap-to-POI interaction
-  on map and sidebar
-
-### Modified Capabilities
-
-- `planner-session`: Waypoint Y.Map objects gain a `note` string field
-- `gpx-export`: Waypoint `<desc>` element populated from notes
-- `shared-types`: `Waypoint` interface extended with optional `note`
-- `planner-map`: POI markers shown near selected waypoint, click to snap
-
-## Non-Goals
-
-- Rich text (bold, links, images) - plain text only
-- Comments from other users - notes belong to the waypoint, not a thread
-- Note history or versioning beyond what Yjs provides
-- Markdown rendering
-- Full OSM data overlay across the entire map (separate feature)
-- POI search or filtering across the whole map viewport
-- Custom POI database - we use OpenStreetMap data exclusively
-- Offline POI data - requires network access to Overpass API
-
-## Impact
-
-- **Yjs schema**: New `note` string key on waypoint Y.Map (backward compatible -
-  old clients ignore unknown keys)
-- **Shared types**: `Waypoint.note?: string` added to `@trails-cool/types`
-- **GPX package**: `generateGpx` writes `<desc>` when waypoint has a note
-- **Sidebar**: Inline note display and editing below waypoint name; POI list
-  under selected waypoint with snap buttons
-- **Map markers**: Note indicator icon and tooltip; POI markers near selected
-  waypoint
-- **New Overpass API client**: Fetches nearby POIs for a given coordinate,
-  with caching and rate limiting
-- **i18n**: New translation keys for note placeholder, labels, POI types,
-  and snap actions (en + de)
-- **No database changes**: Planner is stateless, all state lives in Yjs. POI
-  cache is ephemeral (in-memory, not persisted)