improve configs, update docs

CHANGELOG.md

@@ -2,6 +2,33 @@
 
 ## [Unreleased] — 2026-03-30
 
+### Data ingestion
+
+- **`bincio import strava`** — OAuth2 Strava importer (`bincio/import_/strava.py` + `bincio/import_/cli.py`)
+  - One-shot local OAuth2 callback server (port 8976); opens browser, receives code, exchanges for tokens
+  - Tokens saved to `~/.config/bincio/strava.json`; auto-refreshed on expiry (6h TTL)
+  - Fetches paginated activity list with `after=` timestamp for efficient incremental runs
+  - Per activity: `GET /activities/{id}/streams` → `_strava_to_parsed()` → `compute()` → `write_activity()`
+  - `_patch_from_summary()`: fills `None` metrics from Strava summary when sensors are missing (manual entries, indoor rides)
+  - Sync state persisted in `data_dir/_strava_sync.json` (imported IDs + last sync timestamp)
+  - Rate limit tracking via `X-RateLimit-Usage`; warns at 85% of 15-min window; auto-retries on 429
+  - Credentials read from (in order): CLI flags → env vars → `extract_config.yaml` under `import.strava`
+  - Install: `uv sync --extra strava`
+
+- **Web file upload** — `POST /api/upload` in `bincio/edit/server.py`
+  - Accepts FIT/GPX/TCX (`.gz` variants too); 409 if activity already exists
+  - Runs full extract pipeline inline: `parse_file()` → `compute()` → `write_activity()` → `merge_all()`
+  - Staged to `data_dir/_uploads/` during processing; cleaned up in `finally`
+  - `↑` button in site nav, gated behind `PUBLIC_EDIT_URL`; drag-and-drop modal; auto-redirects on success
+
+- **`extract_config.yaml` is now gitignored** — safe to store credentials under `import.strava`
+  - `StravaConfig` dataclass added to `bincio/extract/config.py`; parsed from `import.strava:` block
+  - `extract_config.example.yaml` is the tracked template
+
+- **Theme-aware heatmap** (`StatsView.svelte`) — `applyIntensity()` now lerps from the correct
+  background colour in both dark (zinc-800 `#27272a`) and light (zinc-200 `#e4e4e7`) modes;
+  `emptyColor` and `baseRgb` reactive to `data-theme` via `MutationObserver`
+
 ### Athlete page
 
 - **`/athlete` page** — three-tab layout: Power Curve · Records · Profile