perf: accelerate policy and memory hot paths

[alexy]

Adds normalized per-operation Criterion coverage and optimizes TypeSec hot paths without changing authorization semantics.

Measured in the shared Linux Docker runner:

• ODRL: 1.25x faster at 1 candidate, 1.74x at 10, 3.11x at 100; indexed miss 1.29x faster
• RBAC: 64-grant tail 253.58 ns to 90.32 ns; simple hit remains near baseline
• Memory latest-10 query: 25.30 ms to 1.14 ms
• Case-insensitive text query: 3.10 ms to 422.94 us
• Keyword search: 1.08 ms to 492.23 us

Verification:

• cargo fmt --all -- --check
• focused RBAC, ODRL, and memory tests
• cargo test -p typesec-memory --all-features
• strict clippy for core/RBAC/ODRL/memory, all targets and features