[WIP] get rid of the is_cosine field

[alexanderguzhva]

This is the change, targeted at lowering the burden of the faiss::cppcontrib::knowhere.

The following the most important things are implemented:

• Remove the is_cosine field
  • All L2 norms are now stored in the memory in the 1 / ||x|| format
• Simplify the hierarchy of knowhere's custom components for FAISS

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: alexanderguzhva

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Details

Needs approval from an approver in each of these files:

• OWNERS [alexanderguzhva]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[mergify]

@alexanderguzhva 🔍 Important: PR Classification Needed!

For efficient project management and a seamless review process, it's essential to classify your PR correctly. Here's how:

1. If you're fixing a bug, label it as kind/bug.
2. For small tweaks (less than 20 lines without altering any functionality), please use kind/improvement.
3. Significant changes that don't modify existing functionalities should be tagged as kind/enhancement.
4. Adjusting APIs or changing functionality? Go with kind/feature.

For any PR outside the kind/improvement category, ensure you link to the associated issue using the format: “issue: #”.

Thanks for your efforts and contribution to the community!.

[alexanderguzhva]

issue: #1501
/kind improvement

[alexanderguzhva]

issue: #1501
/kind improvement