refactor(speech): versioned v1 client

[dbolduc]

Part of the work for #10170

This is a mixed library that already has the cmake/bazel service_dirs infrastructure in place.

---

This change is 

[codecov]

Codecov Report

Base: 93.64% // Head: 93.64% // Increases project coverage by +0.00% 🎉

Coverage data is based on head (bdc0dd8) compared to base (2ec044f).
Patch has no changes to coverable lines.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #10942   +/-   ##
=======================================
  Coverage   93.64%   93.64%           
=======================================
  Files        1717     1717           
  Lines      154878   154878           
=======================================
+ Hits       145037   145041    +4     
+ Misses       9841     9837    -4     

Impacted Files	Coverage Δ
...le/cloud/storage/internal/curl_download_request.cc	88.62% <0.00%> (-0.34%)	⬇️
...cloud/pubsub/internal/subscription_session_test.cc	98.49% <0.00%> (+0.50%)	⬆️
...bigtable/examples/bigtable_hello_instance_admin.cc	83.00% <0.00%> (+2.00%)	⬆️

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

☔ View full report at Codecov.
📢 Do you have feedback about the report comment? Let us know in this issue.