Soft deprecation of load methods requiring metadata parameters + Fix TypedIndex constructor

[stephen29xie]

Related Issues

Changes Made

C++

• TypedIndex.h
  • Add deprecated annotations to TypedIndex constructors that require metadata parameters.
  • Fix one of the TypedIndex constructors. It was incorrectly calling the HierarchicalNSW constructor
    • There were no build issues prior, I don't think we had any tests or code using this constructor that loaded the old version of indexes without a metadata header
  • Add override keyword for overridden methods for readability and error checking
  • Add loadTypedIndexFromFile method, in addition to the existing loadTypedIndexFromStream method

Java

• Index.java
  • Add deprecated annotations to load() methods that require metadata parameters.
• StringIndex.java
  • Add deprecated annotations to load() methods that require metadata parameters.
• regenerated the docs

Python

• No action. nanobind doesn't support deprecation annotations

Testing

Checklist

• My code follows the code style of this project.
• I have added and/or updated appropriate documentation (if applicable).
• All new and existing tests pass locally with these changes.
• I have run static code analysis (if available) and resolved any issues.
• I have considered backward compatibility (if applicable).
• I have confirmed that this PR does not introduce any security vulnerabilities.

Additional Comments

[stephen29xie]

The constructor for HierarchicalNSW is

HierarchicalNSW(Space<dist_t, data_t> *s,
                  std::shared_ptr<InputStream> inputStream,
                  size_t max_elements = 0, bool search_only = false)