Fix/various UI fixes (#605)

* UI: replace textual 'close' with X icon\n\n- AppInfoView (iOS): use xmark icon in nav bar to match Location Notes style.\n- LocationChannelsSheet: use xmark icon for close on iOS/macOS toolbars; add accessibility label.

* Location Notes: prefix usernames with @ and lighten #geohash\n\n- Show @ before usernames in notes list.\n- Split header into '@' and '#geohash' and color the geohash with secondary green for consistency.

* Header spacing: add breathing room between channel badge, notes button, and people count\n\n- Add trailing padding after #mesh/#geohash badge.\n- Add leading padding before notes button and people counter to improve readability.

* Header: nudge #mesh/#geohash badge right with leading padding

* Location Notes + Header polish\n\n- Header: add space in '@ #geohash' and use darker green for geohash.\n- Notes list: render '@name#abcd' with darker green for #abcd to match chat.\n- Header: move geochat bookmark icon after #geohash badge with consistent spacing.

* Location Notes: @name regular green, #abcd darker; nudge #hash\n\n- Render '@' and base name in regular green, suffix '#abcd' in darker green.\n- Add extra left padding before '#geohash' in notes header.\n- Increase leading padding for channel badge to push #mesh/#geohash further right.

* Fix notes icon color: subscribe/count at block-level geohash\n\n- Use block (precision 7) geohash for notes: when opening sheet, on channel changes, and when subscribing the counter.\n- Aligns with LocationNotesManager which publishes at street-level geohash, allowing the counter to detect notes and turn icon blue.

* Header spacing: move #mesh/#geohash closer to notes/bookmark\n\n- Reduce trailing padding on channel badge and leading padding on notes/bookmark to cluster them together.\n- Keeps larger gap before people count for readability.

* Notes: standardize on building-level (8 chars) for publish/read\n\n- Use .building geohash when opening notes, reacting to channel updates, and subscribing the counter.\n- Update comments to reflect building-level scope.

* Location Channels sheet: use black sheet background like other sheets\n\n- Add backgroundColor and apply to container and list.\n- Hide list default background with scrollContentBackground(.hidden).

* Notes icon: use green when notes exist (matches app green)

* Location Channels: boxed 'bookmarked' section; keep 'remove location access' outside box\n\n- Wrap bookmarked list in a rounded, subtle grey box within the list.\n- Ensure the 'remove location access' button is not inside the box and clears list row background.

* Notes counter UX: avoid grey flicker when closing sheet\n\n- Preserve last count during resubscribe to prevent brief 0 state.\n- Keep existing subscription when building geohash temporarily unavailable; only cancel if none or permission revoked.

* Notes counter: unsubscribe without clearing count on resubscribe\n\n- Avoid calling cancel() in subscribe; just unsubscribe old sub to prevent wiping count to 0.\n- Prevents green→grey flicker after closing sheet or location updates.

* Notes icon: use sheet count until counter finishes initial load; don’t zero on sheet close\n\n- Compute hasNotes using max(count, sheetCount) while initialLoadComplete is false.\n- Remove sheetNotesCount reset on sheet disappear to avoid transient grey.

* Location Notes header: remove extra gap before #geohash (drop leading padding)

* Notes sheet: color #abcd suffix as darker green via opacity (match chat)

* Notes sheet: show timestamp in brackets; drop #abcd from @name

* chore: commit remaining local changes

* Header: move notes + bookmark to left of #mesh/#geohash

* Header spacing: tighten gap between #mesh/#geohash and peer count

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Co-authored-by: jack <jackjackbits@users.noreply.github.com>

bitchat/Services/NotificationService.swift

@@ -62,7 +62,7 @@ final class NotificationService {
     }
     
     func sendPrivateMessageNotification(from sender: String, message: String, peerID: String) {
-        let title = "🔒 private message from \(sender)"
+        let title = "🔒 DM from \(sender)"
         let body = message
         let identifier = "private-\(UUID().uuidString)"
         let userInfo = ["peerID": peerID, "senderName": sender]