fix: replace all silent .catch(() => {}) with console.warn (BUG-F2)

13 silent catch handlers replaced with descriptive console.warn logging
across 6 frontend files. No silent error swallowing remains.

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

frontend/src/composables/useNostr.ts

@@ -126,7 +126,7 @@ if (!autoRestoreRan && pubkey.value && !bot.value && getToken() && !isTokenExpir
       bot.value = normalizeBotData(data.bot)
       store('bf_bot', bot.value)
     }
-  }).catch(() => {})
+  }).catch(err => console.warn('[Nostr] auto-restore failed:', err))
 } else if (!autoRestoreRan && pubkey.value && !getToken()) {
   // No JWT — clear stale pubkey from before the JWT migration
   autoRestoreRan = true
@@ -224,7 +224,7 @@ export function useNostr() {
         fetchNostrProfilePic(result.pubkey).then(pic => {
           profilePicUrl.value = pic
           store('bf_pic', pic)
-        }).catch(() => {})
+        }).catch(err => console.warn('[Nostr] relay profile fetch failed:', err))
       } else {
         freshlyGenerated = false
         profilePicUrl.value = null
@@ -285,7 +285,7 @@ export function useNostr() {
       fetchNostrProfilePic(result.pubkey).then(pic => {
         profilePicUrl.value = pic
         store('bf_pic', pic)
-      }).catch(() => {})
+      }).catch(err => console.warn('[Nostr] profile pic fetch failed:', err))
 
       return result
     } finally {