fix: add minitest and rake to Gemfile for CI

Ruby 3.3 requires minitest to be explicitly declared as a dependency
when running under bundle exec. Also adds rake for `rake test`.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: architecture

Gemfile

@@ -1,3 +1,8 @@
 source "https://rubygems.org"
 
 gemspec
+
+group :test do
+  gem "minitest"
+  gem "rake"
+end

Gemfile.lock

@@ -0,0 +1,58 @@
+PATH
+  remote: .
+  specs:
+    elevenlabs (0.3.4)
+      faraday (>= 2.0)
+      faraday-multipart (>= 1.0)
+      json
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    drb (2.2.3)
+    faraday (2.14.1)
+      faraday-net_http (>= 2.0, < 3.5)
+      json
+      logger
+    faraday-multipart (1.2.0)
+      multipart-post (~> 2.0)
+    faraday-net_http (3.4.2)
+      net-http (~> 0.5)
+    json (2.18.1)
+    logger (1.7.0)
+    minitest (6.0.2)
+      drb (~> 2.0)
+      prism (~> 1.5)
+    multipart-post (2.4.1)
+    net-http (0.9.1)
+      uri (>= 0.11.1)
+    prism (1.9.0)
+    rake (13.3.1)
+    uri (1.1.1)
+
+PLATFORMS
+  arm64-darwin-24
+  ruby
+
+DEPENDENCIES
+  elevenlabs!
+  minitest
+  rake
+
+CHECKSUMS
+  drb (2.2.3) sha256=0b00d6fdb50995fe4a45dea13663493c841112e4068656854646f418fda13373
+  elevenlabs (0.3.4)
+  faraday (2.14.1) sha256=a43cceedc1e39d188f4d2cdd360a8aaa6a11da0c407052e426ba8d3fb42ef61c
+  faraday-multipart (1.2.0) sha256=7d89a949693714176f612323ca13746a2ded204031a6ba528adee788694ef757
+  faraday-net_http (3.4.2) sha256=f147758260d3526939bf57ecf911682f94926a3666502e24c69992765875906c
+  json (2.18.1) sha256=fe112755501b8d0466b5ada6cf50c8c3f41e897fa128ac5d263ec09eedc9f986
+  logger (1.7.0) sha256=196edec7cc44b66cfb40f9755ce11b392f21f7967696af15d274dde7edff0203
+  minitest (6.0.2) sha256=db6e57956f6ecc6134683b4c87467d6dd792323c7f0eea7b93f66bd284adbc3d
+  multipart-post (2.4.1) sha256=9872d03a8e552020ca096adadbf5e3cb1cd1cdd6acd3c161136b8a5737cdb4a8
+  net-http (0.9.1) sha256=25ba0b67c63e89df626ed8fac771d0ad24ad151a858af2cc8e6a716ca4336996
+  prism (1.9.0) sha256=7b530c6a9f92c24300014919c9dcbc055bf4cdf51ec30aed099b06cd6674ef85
+  rake (13.3.1) sha256=8c9e89d09f66a26a01264e7e3480ec0607f0c497a861ef16063604b1b08eb19c
+  uri (1.1.1) sha256=379fa58d27ffb1387eaada68c749d1426738bd0f654d812fcc07e7568f5c57c6
+
+BUNDLED WITH
+  4.0.1