fix(companion): hashtag join trims like the app, prefs survive a downgrade, a sender named Me

- Joining #topic drops surrounding spaces and keeps the case, as
  meshcore-open's derivePskFromHashtag() does.
- /prefs written by a newer build (bigger NodePrefs, same version): the
  extra bytes are read through the CRC and skipped instead of resetting
  every setting.
- A channel post from someone named "Me" is filed as "\"Me\": ...", so
  the views don't take it for our own.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

examples/companion_radio/DataStore.cpp

@@ -445,7 +445,18 @@ void DataStore::loadPrefs(NodePrefs& prefs, double& node_lat, double& node_lon)
       ok = file.read((uint8_t*)tmp, n) == (int)n;
       uint32_t crc = crc32(0, (const uint8_t*)&lat, sizeof(lat));
       crc = crc32(crc, (const uint8_t*)&lon, sizeof(lon));
-      ok = ok && crc32(crc, (const uint8_t*)tmp, n) == h.crc;
+      crc = crc32(crc, (const uint8_t*)tmp, n);
+      // Written by a newer build (a downgrade): its extra fields are skipped,
+      // but the CRC covers them, so read them through it rather than losing
+      // every setting to a mismatch.
+      for (size_t left = h.size - n; ok && left > 0; ) {
+        uint8_t buf[32];
+        size_t k = left < sizeof(buf) ? left : sizeof(buf);
+        ok = file.read(buf, k) == (int)k;
+        crc = crc32(crc, buf, k);
+        left -= k;
+      }
+      ok = ok && crc == h.crc;
     }
     file.close();
     if (ok) { prefs = *tmp; node_lat = lat; node_lon = lon; }

examples/companion_radio/ui-core/ChannelControl.h

@@ -113,11 +113,17 @@ static Result addPublic() {
 }
 
 // "#topic": name and passphrase both "#topic" (a leading '#' typed is kept once).
+// Spaces around it are dropped and the case kept, as the phone app does
+// (meshcore-open's derivePskFromHashtag()), so "#Kraków " joins the same channel.
 static Result addHashtag(const char* topic) {
-  if (topic && topic[0] == '#') topic++;
+  if (!topic) return NO_NAME;
-  if (!topic || !topic[0]) return NO_NAME;
+  while (*topic == ' ') topic++;
+  if (topic[0] == '#') topic++;
   char name[32];
   snprintf(name, sizeof(name), "#%s", topic);
+  size_t n = strlen(name);
+  while (n > 1 && name[n - 1] == ' ') name[--n] = '\0';
+  if (n < 2) return NO_NAME;
   uint8_t secret[32];
   phraseToSecret(name, secret);
   return save(freeSlot(), name, secret);

examples/companion_radio/ui-core/UiCore.h

@@ -246,6 +246,11 @@ public:
   }
   void onChannelMessageRecvEx(mesh::Packet *pkt, uint8_t channel_idx, ChannelDetails& channel_details,
                               uint32_t timestamp, const char* text) override {
+    // Our own posts are filed as "Me: ..." and every view reads that prefix as
+    // "ours". Someone else named "Me" gets quotes, so theirs stays theirs (a
+    // bubble on the left, counted unread).
+    char quoted[MSG_TEXT_BUF];
+    if (strncmp(text, "Me: ", 4) == 0) { snprintf(quoted, sizeof(quoted), "\"Me\"%s", text + 2); text = quoted; }
     addChannelMsg(channel_idx, text, timestamp, pkt->path, (uint8_t)pkt->path_len);
     pushMessageArrived(UIEventType::channelMessage, channel_details.name, channel_idx);
   }