Fix Wahoo import bugs, add Import All, update spec

Bugs fixed:
- FIT parser returns timestamps as Date objects, not strings — convert
  to ISO 8601 before passing to generateGpx (caused str.replace crash)
- FIT parser already converts semicircles to degrees — remove redundant
  conversion that produced near-zero coordinates
- Wahoo CDN URLs are pre-signed S3 URLs — remove Bearer auth header
  from download requests (caused 400 "Unsupported Authorization Type")
- Filter out third-party workouts (fitness_app_id >= 1000) since Wahoo
  does not share their data via the API

UX improvements:
- Individual imports use fetcher (no page refresh), button shows
  "Importing..." inline
- "Import all" button imports all unimported workouts on the page
  sequentially with progress indicator
- Add @vitejs/plugin-basic-ssl for local HTTPS dev (opt-in via HTTPS=1)

Also adds unit test for FIT-to-GPX conversion with real fixture file,
and updates wahoo-import spec to reflect all behaviors.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

openspec/specs/wahoo-import/spec.md

@@ -32,11 +32,15 @@ New Wahoo workouts SHALL be automatically imported when they complete.
 #### Scenario: Webhook receives new workout
 - **WHEN** Wahoo sends a `workout_summary` webhook to `/api/sync/webhook/wahoo`
 - **THEN** the system identifies the user via `provider_user_id`
-- **AND** downloads the FIT file from Wahoo's CDN
+- **AND** downloads the FIT file from Wahoo's CDN (without auth headers, as CDN URLs are pre-signed)
 - **AND** converts it to GPX
 - **AND** creates a journal activity with the GPX, stats, and PostGIS geometry
 - **AND** records the import in `sync_imports` to prevent duplicates
 
+#### Scenario: Webhook for workout without file
+- **WHEN** a webhook arrives for a workout with no FIT file URL
+- **THEN** the activity is created without GPX or geometry
+
 #### Scenario: Duplicate webhook
 - **WHEN** a webhook arrives for a workout already imported
 - **THEN** the import is skipped silently (idempotent)
@@ -51,20 +55,46 @@ Users SHALL be able to browse and selectively import older Wahoo workouts.
 #### Scenario: View workout list
 - **WHEN** a user visits the Wahoo import page
 - **THEN** their Wahoo workouts are listed with date, type, duration, and distance
-- **AND** already-imported workouts are marked
+- **AND** already-imported workouts are marked as "Imported"
+- **AND** third-party workouts (fitness_app_id >= 1000) are filtered out, as Wahoo does not share their data via the API
+- **AND** workouts without a FIT file show a "No GPS" badge with a tooltip explaining the provider has no route data
 
-#### Scenario: Import workout
+#### Scenario: Import single workout
 - **WHEN** a user clicks "Import" on a Wahoo workout
-- **THEN** the FIT file is downloaded, converted to GPX, and a new activity is created
+- **THEN** the import runs in the background using a fetcher (no page refresh)
+- **AND** the button shows "Importing..." during the import
+- **AND** changes to "Imported" when complete
+
+#### Scenario: Import all workouts
+- **WHEN** a user clicks "Import all"
+- **THEN** all unimported workouts on the current page are imported sequentially
+- **AND** a progress indicator shows "Importing X of Y..."
+
+### Requirement: Activity import metadata
+Imported activities SHALL show their origin in the UI.
+
+#### Scenario: View imported activity
+- **WHEN** a user views an activity that was imported from Wahoo
+- **THEN** an "Imported from wahoo" badge is displayed on the detail page
+
+#### Scenario: Delete and reimport
+- **WHEN** a user deletes an imported activity
+- **THEN** the sync_imports record is also deleted
+- **AND** the workout appears as importable again on the import page
 
 ### Requirement: FIT to GPX conversion
 The system SHALL convert Wahoo's FIT binary files to GPX format.
 
 #### Scenario: Convert FIT with GPS data
 - **WHEN** a FIT file contains GPS track records
-- **THEN** track points with lat, lon, elevation, and timestamp are extracted
+- **THEN** track points with lat, lon, elevation, and ISO 8601 timestamps are extracted
+- **AND** coordinates are used as-is from the FIT parser (which already converts semicircles to degrees)
 - **AND** a valid GPX string is produced using `generateGpx`
 
 #### Scenario: FIT without GPS data
 - **WHEN** a FIT file has no GPS records (e.g., indoor trainer workout)
 - **THEN** the activity is created without GPX or geometry (stats only)
+
+#### Scenario: Workout without FIT file
+- **WHEN** a workout has no file URL (e.g., aborted recording, third-party app data)
+- **THEN** the activity is created without GPX or geometry