fix(cpp): move bazel build config for bdd/cpp to foreign/cpp

[slbotbm]

In #3662, we were facing a problem: we have two lockfiles in our repo. bdd/cpp declares the sdk as a local dependency, so the sdk's dependencies are also saved into bdd's lockfile. When the sdk's lockfile is updated, bdd's lockfile also needs to be updated, but it does not happen, and there is no way to tell dependabot to update bdd's lockfile.

This pr removes the bazel config inside bdd/cpp and adds a softlink to the c++ files and headers in bdd/cpp, allowing the building of bdd/cpp binary to happen inside foreign/cpp, thus solving the problem of tow lockfiles.

also upgrades bazel to 9.2.0

also reordered the tests/ directory a bit, dividing it into three folders: bdd/, e2e/, and unit/, and changed the file names a bit.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.54%. Comparing base (e51160f) to head (a2f0b76).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #3675      +/-   ##
============================================
- Coverage     73.62%   73.54%   -0.09%     
  Complexity      937      937              
============================================
  Files          1297     1298       +1     
  Lines        143770   144010     +240     
  Branches     119328   119639     +311     
============================================
+ Hits         105849   105910      +61     
- Misses        34556    34640      +84     
- Partials       3365     3460      +95     

Components	Coverage Δ
Rust Core	73.82% <ø> (-0.03%)	⬇️
Java SDK	62.44% <ø> (ø)
C# SDK	71.07% <ø> (-1.11%)	⬇️
Python SDK	92.17% <ø> (ø)
PHP SDK	84.29% <ø> (ø)
Node SDK	91.12% <ø> (-0.24%)	⬇️
Go SDK	42.71% <ø> (ø)
see 48 files with indirect coverage changes

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