fix frozen string bug, add bsky username prefix to searched names

app/helpers/domain/posts_helper.rb

@@ -539,7 +539,7 @@ module Domain::PostsHelper
     return nil if source.blank?
 
     # normalize the source to a lowercase string with a protocol
-    source.downcase!
+    source = source.downcase
     source = "https://" + source unless source.include?("://")
     begin
       uri = URI.parse(source)

app/models/domain/user/bluesky_user.rb

@@ -65,7 +65,12 @@ class Domain::User::BlueskyUser < Domain::User
 
   sig { override.returns(T::Array[String]) }
   def names_for_search
-    [display_name, handle].compact
+    names = [display_name, handle]
+    if (h = handle)&.ends_with?(".bsky.social")
+      names << h.split(".").first
+    end
+    names << did
+    names.compact
   end
 
   sig { override.returns(T.nilable(String)) }

spec/helpers/domain/bluesky_post_helper_spec.rb

@@ -19,6 +19,22 @@ RSpec.describe Domain::BlueskyPostHelper, type: :helper do
       "Hello @alice.bsky.social! Check out https://bsky.app/profile/bob.bsky.social/post/abc123 and #hashtag"
     end
 
+    # Shared test data used across multiple contexts
+    let(:linked_user) do
+      create(
+        :domain_user_bluesky_user,
+        handle: "bob.bsky.social",
+        did: "did:plc:bob123",
+      )
+    end
+    let(:linked_post) do
+      create(
+        :domain_post_bluesky_post,
+        rkey: "abc123",
+        at_uri: "at://did:plc:bob123/app.bsky.feed.post/abc123",
+      )
+    end
+
     context "when facets is nil" do
       it "returns the original text unchanged" do
         result =
@@ -241,13 +257,6 @@ RSpec.describe Domain::BlueskyPostHelper, type: :helper do
     end
 
     context "with link facets" do
-      let(:linked_post) do
-        create(
-          :domain_post_bluesky_post,
-          rkey: "abc123",
-          at_uri: "at://did:plc:bob123/app.bsky.feed.post/abc123",
-        )
-      end
       let(:text) do
         "Check out https://bsky.app/profile/bob.bsky.social/post/abc123"
       end
@@ -270,7 +279,10 @@ RSpec.describe Domain::BlueskyPostHelper, type: :helper do
       end
 
       context "when linked post exists in database" do
-        before { linked_post } # Ensure post exists
+        before do
+          linked_user # Ensure user exists
+          linked_post # Ensure post exists
+        end
 
         it "renders inline_link_domain_post partial" do
           expect(helper).to receive(:render).with(
@@ -378,13 +390,6 @@ RSpec.describe Domain::BlueskyPostHelper, type: :helper do
           did: "did:plc:alice123",
         )
       end
-      let(:linked_post) do
-        create(
-          :domain_post_bluesky_post,
-          rkey: "abc123",
-          at_uri: "at://did:plc:bob123/app.bsky.feed.post/abc123",
-        )
-      end
       let(:text) do
         "Hey @alice.bsky.social, check https://bsky.app/profile/bob.bsky.social/post/abc123 #cool"
       end
@@ -431,6 +436,7 @@ RSpec.describe Domain::BlueskyPostHelper, type: :helper do
 
       before do
         mentioned_user
+        linked_user
         linked_post
       end