Allow setting internal tags and expose numeric tags as metrics

---------

Co-authored-by: Damien Mehala <[email protected]>

Ensure glob matching is case insensitive and add test covering case
sensitivity.

Since GCC 13, std::uint64_t and friends require an explicit include of
`<cstdint>`.
See also https://gcc.gnu.org/gcc-13/porting_to.html#header-dep-changes

Co-authored-by: Paul Meyer <[email protected]>

Add support for W3C datadog tracestate field `p`.

- Collect informations on the Operating System and the CPU architecture.
- Report those informations through APM Telemetry.

- refactor: the codebase to use `substr` instead of `range`.
- refactor: CMake targets.
- refactor: add bazelrc to build using either abseil or std::string STD.
- ci: build and run on windows using CMake and bazel.
- update: add platform support section and update building instructions.

Usage of std::regex_match was problematic for traceparent with trailing
spaces. The overload use is `std::regex_match(str, str + std::char_traits<CharT>::length(str), m, e, flags)`,
which resolves as the whole input instead of the trimmed input.

Changes:
  - Fix std::regex_match usage.
  - Add unit test.

Remove validation on Datadog's W3C tracestate for `p` field.

According to the Remote Configuration specification,
`DD_REMOTE_CONFIG_POLL_INTERVAL_SECONDS` support floating point input
and can be set to `0`.

Now, sampling remote configuration do not create a new trace sampler
which had the side effect to reset the rate limiter.

- add sampling rules RC support
- fix: report telemetry sampling rules
- fix: report telemetry rps and sample rate for span
- report remote trace sample rate as RULE instead of REMOTE_RULE for legacy reasons
- update REMOTE_RULES and REMOTE_ADAPTIVE_RULE values to match the spec
- report default sample rate for telemetry
- add _dd.psr for new remote rules

Reset trace sampling rules legacy order.