Upgrade Capybara to 3.40.0 for Rack 3.2 compatibility

Fixes pre-existing test failures caused by Rack 3.2 incompatibility.

Problem:
- Integration tests failing with: uninitialized constant Rack::Handler
- Rack 3.0+ removed Rack::Handler, but Capybara 3.39.2 still uses it
- This error exists on both master and this branch (confirmed by testing)

Solution:
- Upgrade Capybara from 3.39.2 to ~> 3.40
- Capybara 3.40.0 adds full Rack 3 support (released 2024-01-26)
- Version 3.39.0 had experimental Rack 3 support, 3.40.0 made it official

Testing:
- Verified tests now run without Rack::Handler error
- bundle update capybara successful
- Tests execute (though some still fail due to unrelated issues)

Investigation notes:
- Per CLAUDE.md guidance, confirmed failures are pre-existing on master
- Tested master branch: same Rack::Handler error occurs
- This fix addresses test suite infrastructure, not code changes in this PR

References:
- Capybara changelog: https://github.com/teamcapybara/capybara/blob/master/History.md
- Rack 3 issue: teamcapybara/capybara#2640

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: justin808

Gemfile.development_dependencies

@@ -47,7 +47,7 @@ group :development, :test do
 end
 
 group :test do
-  gem "capybara"
+  gem "capybara", "~> 3.40"
   gem "capybara-screenshot"
   gem "coveralls", require: false
   gem "cypress-on-rails", "~> 1.19"

spec/dummy/Gemfile.lock

@@ -100,11 +100,11 @@ GEM
       msgpack (~> 1.2)
     builder (3.3.0)
     byebug (11.1.3)
-    capybara (3.39.2)
+    capybara (3.40.0)
       addressable
       matrix
       mini_mime (>= 0.1.3)
-      nokogiri (~> 1.8)
+      nokogiri (~> 1.11)
       rack (>= 1.6.0)
       rack-test (>= 0.6.3)
       regexp_parser (>= 1.5, < 3.0)
@@ -177,7 +177,7 @@ GEM
       net-pop
       net-smtp
     marcel (1.1.0)
-    matrix (0.4.2)
+    matrix (0.4.3)
     method_source (1.0.0)
     mini_mime (1.1.5)
     mini_portile2 (2.8.9)
@@ -227,7 +227,7 @@ GEM
     puma (6.4.0)
       nio4r (~> 2.0)
     racc (1.8.1)
-    rack (3.2.1)
+    rack (3.2.4)
     rack-proxy (0.7.7)
       rack
     rack-session (2.1.1)
@@ -276,7 +276,7 @@ GEM
     rdoc (6.14.2)
       erb
       psych (>= 4.0.0)
-    regexp_parser (2.8.1)
+    regexp_parser (2.11.3)
     reline (0.6.2)
       io-console (~> 0.5)
     rexml (3.2.6)
@@ -428,7 +428,7 @@ DEPENDENCIES
   amazing_print
   benchmark
   bootsnap
-  capybara
+  capybara (~> 3.40)
   capybara-screenshot
   coveralls
   cypress-on-rails (~> 1.19)