feat: make chat actions context-aware and filter by membership status

Actions are now intelligently filtered based on the user's membership in
the conversation, providing a cleaner and more intuitive UX.

Changes:
- Added GetActionsOptions type with conversation and activePubkey
- Updated base adapter getActions() to accept optional context
- Modified NIP-29 adapter to filter actions based on membership:
  - /join: only shown when user is NOT a member/admin
  - /leave: only shown when user IS a member
- Updated ChatViewer to pass conversation and user context to searchCommands
- Moved searchCommands callback after conversation is defined

This prevents showing irrelevant commands like "/join" when you're already
a member, or "/leave" when you haven't joined yet. The autocomplete menu
now only displays actions that are actually executable in the current context.

Implementation notes:
- NIP-29 uses getAllActions() fallback when context unavailable
- Membership determined by checking conversation.participants array
- Other protocols return empty array by default (no actions yet)

Tests: All 804 tests passing
Build: Successful
Lint: No new errors

src/components/ChatViewer.tsx

@@ -333,18 +333,6 @@ export function ChatViewer({
   // Get the appropriate adapter for this protocol
   const adapter = useMemo(() => getAdapter(protocol), [protocol]);
 
-  // Slash command search for action autocomplete
-  const searchCommands = useCallback(
-    async (query: string) => {
-      const availableActions = adapter.getActions();
-      const lowerQuery = query.toLowerCase();
-      return availableActions.filter((action) =>
-        action.name.toLowerCase().includes(lowerQuery),
-      );
-    },
-    [adapter],
-  );
-
   // State for retry trigger
   const [retryCount, setRetryCount] = useState(0);
 
@@ -377,6 +365,22 @@ export function ChatViewer({
       ? conversationResult.conversation
       : null;
 
+  // Slash command search for action autocomplete
+  // Context-aware: only shows relevant actions based on membership status
+  const searchCommands = useCallback(
+    async (query: string) => {
+      const availableActions = adapter.getActions({
+        conversation: conversation || undefined,
+        activePubkey: activeAccount?.pubkey,
+      });
+      const lowerQuery = query.toLowerCase();
+      return availableActions.filter((action) =>
+        action.name.toLowerCase().includes(lowerQuery),
+      );
+    },
+    [adapter, conversation, activeAccount],
+  );
+
   // Cleanup subscriptions when conversation changes or component unmounts
   useEffect(() => {
     return () => {

src/lib/chat/adapters/base-adapter.ts

@@ -14,6 +14,7 @@ import type {
   ChatAction,
   ChatActionContext,
   ChatActionResult,
+  GetActionsOptions,
 } from "@/types/chat-actions";
 
 /**
@@ -150,9 +151,10 @@ export abstract class ChatProtocolAdapter {
   /**
    * Get available actions for this protocol
    * Actions are protocol-specific slash commands like /join, /leave, etc.
+   * Can be filtered based on conversation and user context
    * Returns empty array by default
    */
-  getActions(): ChatAction[] {
+  getActions(_options?: GetActionsOptions): ChatAction[] {
     return [];
   }
 
@@ -164,7 +166,11 @@ export abstract class ChatProtocolAdapter {
     actionName: string,
     context: ChatActionContext,
   ): Promise<ChatActionResult> {
-    const action = this.getActions().find((a) => a.name === actionName);
+    // Get actions with context for validation
+    const action = this.getActions({
+      conversation: context.conversation,
+      activePubkey: context.activePubkey,
+    }).find((a) => a.name === actionName);
 
     if (!action) {
       return {

src/lib/chat/adapters/nip-29-adapter.ts

@@ -13,7 +13,7 @@ import type {
   ParticipantRole,
 } from "@/types/chat";
 import type { NostrEvent } from "@/types/nostr";
-import type { ChatAction } from "@/types/chat-actions";
+import type { ChatAction, GetActionsOptions } from "@/types/chat-actions";
 import eventStore from "@/services/event-store";
 import pool from "@/services/relay-pool";
 import { publishEventToRelays } from "@/services/hub";
@@ -493,9 +493,84 @@ export class Nip29Adapter extends ChatProtocolAdapter {
 
   /**
    * Get available actions for NIP-29 groups
-   * Returns simple join/leave commands without parameters
+   * Filters actions based on user's membership status:
+   * - /join: only shown when user is NOT a member/admin
+   * - /leave: only shown when user IS a member
    */
-  getActions(): ChatAction[] {
+  getActions(options?: GetActionsOptions): ChatAction[] {
+    const actions: ChatAction[] = [];
+
+    // Check if we have context to filter actions
+    if (!options?.conversation || !options?.activePubkey) {
+      // No context - return all actions
+      return this.getAllActions();
+    }
+
+    const { conversation, activePubkey } = options;
+
+    // Find user's participant info
+    const userParticipant = conversation.participants.find(
+      (p) => p.pubkey === activePubkey,
+    );
+
+    const isMember = !!userParticipant;
+
+    // Add /join if user is NOT a member
+    if (!isMember) {
+      actions.push({
+        name: "join",
+        description: "Request to join the group",
+        handler: async (context) => {
+          try {
+            await this.joinConversation(context.conversation);
+            return {
+              success: true,
+              message: "Join request sent",
+            };
+          } catch (error) {
+            return {
+              success: false,
+              message:
+                error instanceof Error ? error.message : "Failed to join group",
+            };
+          }
+        },
+      });
+    }
+
+    // Add /leave if user IS a member
+    if (isMember) {
+      actions.push({
+        name: "leave",
+        description: "Leave the group",
+        handler: async (context) => {
+          try {
+            await this.leaveConversation(context.conversation);
+            return {
+              success: true,
+              message: "You left the group",
+            };
+          } catch (error) {
+            return {
+              success: false,
+              message:
+                error instanceof Error
+                  ? error.message
+                  : "Failed to leave group",
+            };
+          }
+        },
+      });
+    }
+
+    return actions;
+  }
+
+  /**
+   * Get all possible actions (used when no context available)
+   * @private
+   */
+  private getAllActions(): ChatAction[] {
     return [
       {
         name: "join",

src/types/chat-actions.ts

@@ -35,3 +35,14 @@ export interface ChatAction {
   /** Handler function */
   handler: (context: ChatActionContext) => Promise<ChatActionResult>;
 }
+
+/**
+ * Options for filtering available actions
+ */
+export interface GetActionsOptions {
+  /** Current conversation */
+  conversation?: Conversation;
+
+  /** Active user's pubkey */
+  activePubkey?: string;
+}