Fix common depending on configuration in CMake targets

[matthiaskessler]

Fix common depending on configuration in CMake targets

"common" is a foundational, header-only interface used by dozens of
libraries, while "configuration" is executable-specific. "common"
had ended up linking "configuration" directly, inverting the
intended dependency direction and forcing every consumer of
"common" to transitively depend on an application's configuration.

• Remove the leftover duplicate "commonImpl" target from
  executables/referenceApp/configuration/CMakeLists.txt; its source
  file was already compiled into "configuration" and nothing linked
  against it.
• Restore libs/bsw/common as a pure INTERFACE library (include dirs,
  etl, platform) with no reference to "configuration".
• Have "configuration" (referenceApp and unitTest variants) link
  PUBLIC "common", the correct direction.
• common::busid::BusIdTraits::getName() is declared in "common" but
  implemented in each executable's "configuration" library.
  libs/bsw/transport and platforms/s32k1xx/bsp/canflex2Transceiver
  call it directly, so link "configuration" PUBLIC from those
  targets themselves, matching the existing precedent in
  libs/bsw/uds. Reorder link lists so "configuration" appears after
  "transport", since static libraries are resolved left to right.

Add a "module + moduleImpl" section to
doc/dev/guidelines/module.rst describing this pattern: keep the
generic interface target free of implementation-specific
dependencies, and put those in a separate impl target instead.

[rolandreichweinbmw]

LGTM - just rebase to resolve the documentation merge conflict.