Add inline, remove unused exception variable name, safe float computation

[mnorris11]

This is a patch to get it to work internally. It would be easier if things are in SVS, so next version upgrade we don't need to apply this patch.

Reason for changes:

1. inlining: This is from -Werror,-Winline-namespace-reopened-noninline.
2. Unused exception parameter: -Werror,-Wunused-exception-parameter.
3. Float change: acccording to AI: the shift 125 - e goes out of range for uint32_t when e is outside [102, 112]. The result is multiplied by zero so it's "dead" at runtime, but the shift itself is still UB. UBSAN catches it and 5 FP16 tests fail: WriteAndReadIndexSVSFP16, VamanaFP16TrainSaveLoadAndAdd, WriteAndReadStaticIVFFP16, WriteAndReadIndexSVSIVFFP16, IVFFP16TrainAndAdd.
4. index.h Thread clamping: per AI: "compute_centroid_distances (in common.h:675) partitions centroids across threads using StaticPartition(num_centroids). If you have more threads than centroids, some threads get an empty partition. The callback then calls batch.start() and batch.size() on those empty ranges, leading to OOB access into centroids.get_datum() and matmul_results[tid]. The fix clamps the thread pool size to at most the number of centroids at construction time, so every thread gets at least one centroid to work on."
5. sorted_buffer.h change: " back() returns candidates_[size_ - 1]. When the buffer is empty (size_ == 0), that underflows to candidates_[SIZE_MAX] — an OOB read. The original code evaluated back() before checking full(), so on an empty buffer it would access garbage memory before full() returned false and short-circuited the &&. Swapping the operands ensures full() is checked first; if the buffer isn't full, back() is never called. Classic short-circuit evaluation fix."

[rfsaliev]

Thank you @mnorris11 , for the contribution.
There are some suggestions, proposals and comments

[rfsaliev]

Suggested change

	} catch (const ThreadCrashedError&) {
	} catch (const ThreadCrashedError& SVS_UNUSED(err)) {

[rfsaliev]

Please, use SVS formatting rules.

[rfsaliev]

IMHO, this change will negatively affect usability and maintainability for further API major versions.
Instead, a macro can be used here which value defined in version.h depending on SVS_RUNTIME_API_VERSION, e.g.:

#if (SVS_RUNTIME_API_VERSION == 0)
...
#define SVS_API_V0 inline namespace v0
...
#endif

With usage aka:

Suggested change

	namespace svs {
	namespace runtime {
	namespace v0 {
	inline namespace v0 {
	namespace svs {
	namespace runtime {
	SVS_API_V0 {
	...
	} // SVS_API_V0

[rfsaliev]

Thank you @mnorris11 for the PR.
Unfortunately, more complicated changes had to be applied for proper fixes.
There are created 3 separate PRs based on your proposal:

• [CPPRuntime] Fix C++ Runtime Clang compilation errors #328
• Refactor thread pool creation to validate thread count against centroids #329
• Refactor float_to_float16_untyped_slow for clarity and optimization #330