* add basic functions for working with f32/f64 vectors
* add header file
* fix comment style
* add generic code for working with vectors
* register vector functions
* fix edge cases in vector extract impl
* add static flag for vector (will be used later)
* add basic TCL-based tests
* guard vector functions with SQLITE_OMIT_VECTOR
* adjust build scripts
* delete libsql_vector_idx from this branch
* add one more test
* update bundles
* fix asserts
* fix constants (#define-s are universal but const int doesn't recognized by all compilers)
* update bundles
* review fixes
* build bundles
* add comment about linking math library
