feat(phase5): docs channels - CRUD, wiki sidebar, markdown editor

internal/db/db.go

@@ -408,6 +408,19 @@ CREATE TABLE IF NOT EXISTS event_rsvps (
 
 CREATE INDEX IF NOT EXISTS idx_event_rsvps_event ON event_rsvps(event_id);
 
+-- Documents (wiki/docs channels)
+CREATE TABLE IF NOT EXISTS documents (
+	id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+	channel_id UUID NOT NULL REFERENCES channels(id) ON DELETE CASCADE,
+	creator_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+	title VARCHAR(255) NOT NULL,
+	content TEXT NOT NULL DEFAULT '',
+	created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+	updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+CREATE INDEX IF NOT EXISTS idx_documents_channel ON documents(channel_id, updated_at DESC);
+
 -- Message full-text search
 ALTER TABLE messages ADD COLUMN IF NOT EXISTS search_vector tsvector;
 CREATE INDEX IF NOT EXISTS idx_messages_search ON messages USING GIN(search_vector);