…er (#903)

Changed upsert(), insert(), and replace() to take Document by value
instead of const Document&. This correctly supports:
- lvalues → copied (backward compatible)
- rvalues → moved (was broken before)

The previous signature const Document& with std::move() internally
caused compilation errors since std::move on a const lvalue produces
an rvalue reference that cannot bind to non-const lvalue parameters.

As part of the effort to migrate the C++ FIT performer from the
transactions-fit-performer repository into the C++ SDK, this commit
imports the system_metrics library.

This is the first step in making the C++ SDK self-contained for FIT
testing, allowing the performer to be built and released as part of
the SDK.

The commit also adds a new 'cbc sysinfo' command to the cbc tool as
an integration test for the library.

Examples:

  cbc sysinfo
  cbc sysinfo --pid 3580
  cbc sysinfo --pid 3580 --json
  cbc sysinfo --pid 3580 --json --poll 2

Changes
---------
* Update regex for parsing curl.se Mozilla certs header date
* Output warning if certs header date not found

Co-authored-by: Copilot Autofix powered by AI <[email protected]>

---------

Co-authored-by: Copilot Autofix powered by AI <[email protected]>