Replace per-item sha256 + blake2b in memory_index bloom filter

[Aaryan-Dadu]

Each bloom filter insertion and probe calls blake2b + sha256 on the string.

[riteshngr]

/assign

[mini-walkerx]

✅ Successfully assigned to @riteshngr.

You have 3 hours to complete this issue (Deadline: Sat, 11 Apr 2026 13:28:45 GMT).

[riteshngr]

/unassign

[mini-walkerx]

✅ Successfully unassigned @riteshngr. Waitlist queue triggers to be processed here.

[manasvisharma2231]

/assign

[mini-walkerx]

✅ Successfully assigned to @manasvisharma2231.

You have 3 hours to complete this issue (Deadline: Sat, 11 Apr 2026 17:51:35 GMT).

[manasvisharma2231]

/unassign

[mini-walkerx]

✅ Successfully unassigned @manasvisharma2231. Waitlist queue triggers to be processed here.

[Phantom0299]

/assign