* Replace old repository links & improve README

* Apply suggestion from @yawkat

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Co-authored-by: Jonas Konrad <[email protected]>

This matches the original Ant build:
https://github.com/lz4/lz4-java/blob/be9ce5759ec6cce99544c7112e434be11aedb1a8/build.xml#L336

- added builder for LZ4BlockInputStream which accepts both fast and safe decompressor (prefers fast one)

Co-authored-by: Mihhail Meshkov <[email protected]>

)

An ArrayIndexOutOfBoundsException could indicate either an out-of-bounds access, or invalid arguments (e.g. offset < 0). Since we want to detect the former in the fuzz tests, we need to make sure the latter doesn't happen. This PR:

- Disables the ArrayIndexOutOfBoundsException catch so that it's reported by the fuzzer
- Fixes a bug in the test where the src length was larger than allowed
- Adjusts the LZ4JNIFastDecompressor to throw an LZ4Exception on empty input rather than an ArrayIndexOutOfBoundsExceptions (made by @Marcono1234; not security relevant, this only changes the exception. LZ4JNIFastDecompressor is also disabled by default due to CVE-2025-12183)

With these changes, a quick fuzz run now only shows the native_fast_* tests failing, both with a segfault, which is expected due to CVE-2025-12183.