Rename optional lookup to find(), add throwing get(), and provide
getInt/getPositiveInt/getPositiveNonZeroInt with optional defaults so
callers own missing-key policy without baking domain period semantics
into spinscale.
Co-authored-by: Cursor <cursoragent@cursor.com>
Boost 1.90 marks deadline_timer deprecated; keep historical type aliases so existing spinscale tests need no renames.
Co-authored-by: Cursor <cursoragent@cursor.com>
Move ProbeComponentThreadHarness into spinscale_probe_support (sscl::probe) so tools can link it without gtest; keep a sscl::tests compatibility shim.
Co-authored-by: Cursor <cursoragent@cursor.com>