Fix European trip return heuristic for weekend location tracking

Adjust European short trip heuristic from >3 days to >1 day to correctly
detect when user has returned home from European trips. This fixes the
April 29-30, 2023 case where the location incorrectly showed "Sankt Georg, Hamburg"
instead of "Bristol" when the user was free (no events scheduled) after
the foss-north trip ended on April 27.

The previous logic required more than 3 days to pass before assuming
return home from European countries, but for short European trips by
rail/ferry, users typically return within 1-2 days.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

node_modules/merge-stream/LICENSE

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+The MIT License (MIT)
+
+Copyright (c) Stephen Sugden <me@stephensugden.com> (stephensugden.com)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

node_modules/merge-stream/README.md

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+# merge-stream
+
+Merge (interleave) a bunch of streams.
+
+[![build status](https://secure.travis-ci.org/grncdr/merge-stream.svg?branch=master)](http://travis-ci.org/grncdr/merge-stream)
+
+## Synopsis
+
+```javascript
+var stream1 = new Stream();
+var stream2 = new Stream();
+
+var merged = mergeStream(stream1, stream2);
+
+var stream3 = new Stream();
+merged.add(stream3);
+merged.isEmpty();
+//=> false
+```
+
+## Description
+
+This is adapted from [event-stream](https://github.com/dominictarr/event-stream) separated into a new module, using Streams3.
+
+## API
+
+### `mergeStream`
+
+Type: `function`
+
+Merges an arbitrary number of streams. Returns a merged stream.
+
+#### `merged.add`
+
+A method to dynamically add more sources to the stream. The argument supplied to `add` can be either a source or an array of sources.
+
+#### `merged.isEmpty`
+
+A method that tells you if the merged stream is empty.
+
+When a stream is "empty" (aka. no sources were added), it could not be returned to a gulp task.
+
+So, we could do something like this:
+
+```js
+stream = require('merge-stream')();
+// Something like a loop to add some streams to the merge stream
+// stream.add(streamA);
+// stream.add(streamB);
+return stream.isEmpty() ? null : stream;
+```
+
+## Gulp example
+
+An example use case for **merge-stream** is to combine parts of a task in a project's **gulpfile.js** like this:
+
+```js
+const gulp =          require('gulp');
+const htmlValidator = require('gulp-w3c-html-validator');
+const jsHint =        require('gulp-jshint');
+const mergeStream =   require('merge-stream');
+
+function lint() {
+  return mergeStream(
+    gulp.src('src/*.html')
+      .pipe(htmlValidator())
+      .pipe(htmlValidator.reporter()),
+    gulp.src('src/*.js')
+      .pipe(jsHint())
+      .pipe(jsHint.reporter())
+  );
+}
+gulp.task('lint', lint);
+```
+
+## License
+
+MIT

node_modules/merge-stream/index.js

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+'use strict';
+
+const { PassThrough } = require('stream');
+
+module.exports = function (/*streams...*/) {
+  var sources = []
+  var output  = new PassThrough({objectMode: true})
+
+  output.setMaxListeners(0)
+
+  output.add = add
+  output.isEmpty = isEmpty
+
+  output.on('unpipe', remove)
+
+  Array.prototype.slice.call(arguments).forEach(add)
+
+  return output
+
+  function add (source) {
+    if (Array.isArray(source)) {
+      source.forEach(add)
+      return this
+    }
+
+    sources.push(source);
+    source.once('end', remove.bind(null, source))
+    source.once('error', output.emit.bind(output, 'error'))
+    source.pipe(output, {end: false})
+    return this
+  }
+
+  function isEmpty () {
+    return sources.length == 0;
+  }
+
+  function remove (source) {
+    sources = sources.filter(function (it) { return it !== source })
+    if (!sources.length && output.readable) { output.end() }
+  }
+}

node_modules/merge-stream/package.json

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+{
+  "name": "merge-stream",
+  "version": "2.0.0",
+  "description": "Create a stream that emits events from multiple other streams",
+  "files": [
+    "index.js"
+  ],
+  "scripts": {
+    "test": "istanbul cover test.js && istanbul check-cover --statements 100 --branches 100"
+  },
+  "repository": "grncdr/merge-stream",
+  "author": "Stephen Sugden <me@stephensugden.com>",
+  "license": "MIT",
+  "dependencies": {},
+  "devDependencies": {
+    "from2": "^2.0.3",
+    "istanbul": "^0.4.5"
+  }
+}