Add progressive web app companion for cross-platform access

Vite + TypeScript PWA that mirrors the Android app's core features:
- Pre-processed shelter data (build-time UTM33N→WGS84 conversion)
- Leaflet map with shelter markers, user location, and offline tiles
- Canvas compass arrow (ported from DirectionArrowView.kt)
- IndexedDB shelter cache with 7-day staleness check
- Service worker with CacheFirst tiles and precached app shell
- i18n for en, nb, nn (ported from Android strings.xml)
- iOS/Android compass handling with low-pass filter
- Respects user map interaction (no auto-snap on pan/zoom)
- Build revision cache-breaker for reliable SW updates

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

pwa/node_modules/tr46/LICENSE.md

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+The MIT License (MIT)
+
+Copyright (c) 2016 Sebastian Mayr
+
+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.

pwa/node_modules/tr46/README.md

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+# tr46.js
+
+> An implementation of the [Unicode TR46 specification](http://unicode.org/reports/tr46/).
+
+
+## Installation
+
+[Node.js](http://nodejs.org) `>= 6` is required. To install, type this at the command line:
+```shell
+npm install tr46
+```
+
+
+## API
+
+### `toASCII(domainName[, options])`
+
+Converts a string of Unicode symbols to a case-folded Punycode string of ASCII symbols.
+
+Available options:
+* [`checkBidi`](#checkBidi)
+* [`checkHyphens`](#checkHyphens)
+* [`checkJoiners`](#checkJoiners)
+* [`processingOption`](#processingOption)
+* [`useSTD3ASCIIRules`](#useSTD3ASCIIRules)
+* [`verifyDNSLength`](#verifyDNSLength)
+
+### `toUnicode(domainName[, options])`
+
+Converts a case-folded Punycode string of ASCII symbols to a string of Unicode symbols.
+
+Available options:
+* [`checkBidi`](#checkBidi)
+* [`checkHyphens`](#checkHyphens)
+* [`checkJoiners`](#checkJoiners)
+* [`useSTD3ASCIIRules`](#useSTD3ASCIIRules)
+
+
+## Options
+
+### `checkBidi`
+Type: `Boolean`  
+Default value: `false`  
+When set to `true`, any bi-directional text within the input will be checked for validation.
+
+### `checkHyphens`
+Type: `Boolean`  
+Default value: `false`  
+When set to `true`, the positions of any hyphen characters within the input will be checked for validation.
+
+### `checkJoiners`
+Type: `Boolean`  
+Default value: `false`  
+When set to `true`, any word joiner characters within the input will be checked for validation.
+
+### `processingOption`
+Type: `String`  
+Default value: `"nontransitional"`  
+When set to `"transitional"`, symbols within the input will be validated according to the older IDNA2003 protocol. When set to `"nontransitional"`, the current IDNA2008 protocol will be used.
+
+### `useSTD3ASCIIRules`
+Type: `Boolean`  
+Default value: `false`  
+When set to `true`, input will be validated according to [STD3 Rules](http://unicode.org/reports/tr46/#STD3_Rules).
+
+### `verifyDNSLength`
+Type: `Boolean`  
+Default value: `false`  
+When set to `true`, the length of each DNS label within the input will be checked for validation.

pwa/node_modules/tr46/index.js

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+"use strict";
+
+const punycode = require("punycode");
+const regexes = require("./lib/regexes.js");
+const mappingTable = require("./lib/mappingTable.json");
+
+function containsNonASCII(str) {
+  return /[^\x00-\x7F]/.test(str);
+}
+
+function findStatus(val, { useSTD3ASCIIRules }) {
+  let start = 0;
+  let end = mappingTable.length - 1;
+
+  while (start <= end) {
+    const mid = Math.floor((start + end) / 2);
+
+    const target = mappingTable[mid];
+    if (target[0][0] <= val && target[0][1] >= val) {
+      if (target[1].startsWith("disallowed_STD3_")) {
+        const newStatus = useSTD3ASCIIRules ? "disallowed" : target[1].slice(16);
+        return [newStatus, ...target.slice(2)];
+      }
+      return target.slice(1);
+    } else if (target[0][0] > val) {
+      end = mid - 1;
+    } else {
+      start = mid + 1;
+    }
+  }
+
+  return null;
+}
+
+function mapChars(domainName, { useSTD3ASCIIRules, processingOption }) {
+  let hasError = false;
+  let processed = "";
+
+  for (const ch of domainName) {
+    const [status, mapping] = findStatus(ch.codePointAt(0), { useSTD3ASCIIRules });
+
+    switch (status) {
+      case "disallowed":
+        hasError = true;
+        processed += ch;
+        break;
+      case "ignored":
+        break;
+      case "mapped":
+        processed += mapping;
+        break;
+      case "deviation":
+        if (processingOption === "transitional") {
+          processed += mapping;
+        } else {
+          processed += ch;
+        }
+        break;
+      case "valid":
+        processed += ch;
+        break;
+    }
+  }
+
+  return {
+    string: processed,
+    error: hasError
+  };
+}
+
+function validateLabel(label, { checkHyphens, checkBidi, checkJoiners, processingOption, useSTD3ASCIIRules }) {
+  if (label.normalize("NFC") !== label) {
+    return false;
+  }
+
+  const codePoints = Array.from(label);
+
+  if (checkHyphens) {
+    if ((codePoints[2] === "-" && codePoints[3] === "-") ||
+        (label.startsWith("-") || label.endsWith("-"))) {
+      return false;
+    }
+  }
+
+  if (label.includes(".") ||
+      (codePoints.length > 0 && regexes.combiningMarks.test(codePoints[0]))) {
+    return false;
+  }
+
+  for (const ch of codePoints) {
+    const [status] = findStatus(ch.codePointAt(0), { useSTD3ASCIIRules });
+    if ((processingOption === "transitional" && status !== "valid") ||
+        (processingOption === "nontransitional" &&
+         status !== "valid" && status !== "deviation")) {
+      return false;
+    }
+  }
+
+  // https://tools.ietf.org/html/rfc5892#appendix-A
+  if (checkJoiners) {
+    let last = 0;
+    for (const [i, ch] of codePoints.entries()) {
+      if (ch === "\u200C" || ch === "\u200D") {
+        if (i > 0) {
+          if (regexes.combiningClassVirama.test(codePoints[i - 1])) {
+            continue;
+          }
+          if (ch === "\u200C") {
+            // TODO: make this more efficient
+            const next = codePoints.indexOf("\u200C", i + 1);
+            const test = next < 0 ? codePoints.slice(last) : codePoints.slice(last, next);
+            if (regexes.validZWNJ.test(test.join(""))) {
+              last = i + 1;
+              continue;
+            }
+          }
+        }
+        return false;
+      }
+    }
+  }
+
+  // https://tools.ietf.org/html/rfc5893#section-2
+  if (checkBidi) {
+    let rtl;
+
+    // 1
+    if (regexes.bidiS1LTR.test(codePoints[0])) {
+      rtl = false;
+    } else if (regexes.bidiS1RTL.test(codePoints[0])) {
+      rtl = true;
+    } else {
+      return false;
+    }
+
+    if (rtl) {
+      // 2-4
+      if (!regexes.bidiS2.test(label) ||
+          !regexes.bidiS3.test(label) ||
+          (regexes.bidiS4EN.test(label) && regexes.bidiS4AN.test(label))) {
+        return false;
+      }
+    } else if (!regexes.bidiS5.test(label) ||
+               !regexes.bidiS6.test(label)) { // 5-6
+      return false;
+    }
+  }
+
+  return true;
+}
+
+function isBidiDomain(labels) {
+  const domain = labels.map(label => {
+    if (label.startsWith("xn--")) {
+      try {
+        return punycode.decode(label.substring(4));
+      } catch (err) {
+        return "";
+      }
+    }
+    return label;
+  }).join(".");
+  return regexes.bidiDomain.test(domain);
+}
+
+function processing(domainName, options) {
+  const { processingOption } = options;
+
+  // 1. Map.
+  let { string, error } = mapChars(domainName, options);
+
+  // 2. Normalize.
+  string = string.normalize("NFC");
+
+  // 3. Break.
+  const labels = string.split(".");
+  const isBidi = isBidiDomain(labels);
+
+  // 4. Convert/Validate.
+  for (const [i, origLabel] of labels.entries()) {
+    let label = origLabel;
+    let curProcessing = processingOption;
+    if (label.startsWith("xn--")) {
+      try {
+        label = punycode.decode(label.substring(4));
+        labels[i] = label;
+      } catch (err) {
+        error = true;
+        continue;
+      }
+      curProcessing = "nontransitional";
+    }
+
+    // No need to validate if we already know there is an error.
+    if (error) {
+      continue;
+    }
+    const validation = validateLabel(label, Object.assign({}, options, {
+      processingOption: curProcessing,
+      checkBidi: options.checkBidi && isBidi
+    }));
+    if (!validation) {
+      error = true;
+    }
+  }
+
+  return {
+    string: labels.join("."),
+    error
+  };
+}
+
+function toASCII(domainName, {
+  checkHyphens = false,
+  checkBidi = false,
+  checkJoiners = false,
+  useSTD3ASCIIRules = false,
+  processingOption = "nontransitional",
+  verifyDNSLength = false
+} = {}) {
+  if (processingOption !== "transitional" && processingOption !== "nontransitional") {
+    throw new RangeError("processingOption must be either transitional or nontransitional");
+  }
+
+  const result = processing(domainName, {
+    processingOption,
+    checkHyphens,
+    checkBidi,
+    checkJoiners,
+    useSTD3ASCIIRules
+  });
+  let labels = result.string.split(".");
+  labels = labels.map(l => {
+    if (containsNonASCII(l)) {
+      try {
+        return "xn--" + punycode.encode(l);
+      } catch (e) {
+        result.error = true;
+      }
+    }
+    return l;
+  });
+
+  if (verifyDNSLength) {
+    const total = labels.join(".").length;
+    if (total > 253 || total === 0) {
+      result.error = true;
+    }
+
+    for (let i = 0; i < labels.length; ++i) {
+      if (labels[i].length > 63 || labels[i].length === 0) {
+        result.error = true;
+        break;
+      }
+    }
+  }
+
+  if (result.error) {
+    return null;
+  }
+  return labels.join(".");
+}
+
+function toUnicode(domainName, {
+  checkHyphens = false,
+  checkBidi = false,
+  checkJoiners = false,
+  useSTD3ASCIIRules = false
+} = {}) {
+  const result = processing(domainName, {
+    processingOption: "nontransitional",
+    checkHyphens,
+    checkBidi,
+    checkJoiners,
+    useSTD3ASCIIRules
+  });
+
+  return {
+    domain: result.string,
+    error: result.error
+  };
+}
+
+module.exports = {
+  toASCII,
+  toUnicode
+};

pwa/node_modules/tr46/package.json

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+{
+  "name": "tr46",
+  "version": "1.0.1",
+  "description": "An implementation of the Unicode TR46 spec",
+  "main": "index.js",
+  "files": [
+    "index.js",
+    "lib/mappingTable.json",
+    "lib/regexes.js"
+  ],
+  "scripts": {
+    "test": "mocha",
+    "lint": "eslint .",
+    "pretest": "node scripts/getLatestTests.js",
+    "prepublish": "node scripts/generateMappingTable.js && node scripts/generateRegexes.js"
+  },
+  "repository": "Sebmaster/tr46.js",
+  "keywords": [
+    "unicode",
+    "tr46",
+    "url",
+    "whatwg"
+  ],
+  "author": "Sebastian Mayr <npm@smayr.name>",
+  "license": "MIT",
+  "dependencies": {
+    "punycode": "^2.1.0"
+  },
+  "devDependencies": {
+    "eslint": "^3.13.0",
+    "mocha": "^3.2.0",
+    "regenerate": "^1.3.2",
+    "request": "^2.79.0",
+    "unicode-10.0.0": "^0.7.4"
+  },
+  "unicodeVersion": "10.0.0"
+}