fix(concord): open a channel we can actually read

The channel summary carried only id and name, so the UI could not tell a
readable channel from a locked one and simply took the first. Landing in a
private channel we hold no key for renders empty and refuses every send, which
reads as the community being broken rather than as one channel being locked.

Summaries now carry `private` + `readable`, and navigation prefers a readable
channel — falling back to the first when nothing is readable, so a community
can never become unopenable.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Author: JSKitty

src-tauri/src/commands/community.rs

@@ -98,6 +98,12 @@ pub struct CommunitySummary {
 pub struct ChannelSummary {
     pub channel_id: String,
     pub name: String,
+    /// CORD-03 private channel. Always false for v1, which has none.
+    pub private: bool,
+    /// Whether we hold this channel's key. A private channel we are not (yet)
+    /// granted reads false — the UI must not default to one, since it renders
+    /// empty and refuses every send.
+    pub readable: bool,
 }
 
 fn summarize(community: &vector_core::community::Community) -> CommunitySummary {
@@ -119,7 +125,7 @@ fn summarize(community: &vector_core::community::Community) -> CommunitySummary
         channels: community
             .channels
             .iter()
-            .map(|c| ChannelSummary { channel_id: c.id.to_hex(), name: c.name.clone() })
+            .map(|c| ChannelSummary { channel_id: c.id.to_hex(), name: c.name.clone(), private: false, readable: true })
             .collect(),
         owner_npub,
         dissolved: community.dissolved,
@@ -147,6 +153,8 @@ fn summarize_v2(c: &vector_core::community::v2::community::CommunityV2) -> Commu
             .map(|ch| ChannelSummary {
                 channel_id: vector_core::simd::hex::bytes_to_hex_32(&ch.id.0),
                 name: ch.name.clone(),
+                private: ch.private,
+                readable: !ch.private || ch.key.is_some(),
             })
             .collect(),
         owner_npub: owner.and_then(|pk| pk.to_bech32().ok()),

src/main.js

@@ -2090,6 +2090,8 @@ async function surfaceCommunitySummary(summary) {
     if (!summary) return null;
     let firstChannel = null;
     let firstSync = null;
+    let fallbackChannel = null;
+    let fallbackSync = null;
     for (const ch of summary.channels || []) {
         const chat = getOrCreateChat(ch.channel_id, 'Community');
         chat.metadata = chat.metadata || {};
@@ -2118,17 +2120,24 @@ async function surfaceCommunitySummary(summary) {
         // The page-1 sync pulls existing history (e.g. the owner's welcome message) so the
         // channel isn't empty on open. Backend anti-stampede dedups a later open.
         const p = invoke('sync_community_channel', { channelId: ch.channel_id, beforeMs: null }).catch(() => {});
-        if (!firstChannel) { firstChannel = ch.channel_id; firstSync = p; }
+        // Navigate to a channel we can actually READ. A private channel we hold no
+        // key for renders empty and refuses every send, so landing there reads as
+        // the community being broken. Falls back to the first channel when nothing
+        // is readable, so a community never becomes unopenable.
+        if (ch.readable !== false && !firstChannel) { firstChannel = ch.channel_id; firstSync = p; }
+        if (!fallbackChannel) { fallbackChannel = ch.channel_id; fallbackSync = p; }
     }
     loadCommunityRoles(summary.community_id);
     resolveCommunityAvatars();
     renderChatlist();
     // If a warmed preload was promoted on Accept, the chat is ALREADY populated (its messages were
     // emitted by the backend), so open immediately — the first sync trues it up in the background.
     // Only await the sync when NOT preloaded (a cold join would otherwise open to an empty chat).
-    if (firstSync && !summary.preloaded) await firstSync;
+    const openChannel = firstChannel || fallbackChannel;
+    const openSync = firstChannel ? firstSync : fallbackSync;
+    if (openSync && !summary.preloaded) await openSync;
     renderChatlist();
-    return firstChannel;
+    return openChannel;
 }
 
 /**