refactor(zkvm): move e2e tests out of prover

[aproskill81]

Summary

Move guest-level zkVM end-to-end tests out of jolt-core/src/zkvm/prover.rs into a dedicated jolt-core/src/zkvm/e2e_tests.rs module.

This keeps prover.rs focused on prover logic and prover-coupled tests, while preserving the existing e2e coverage in a layout that is easier to extend for future Dory configuration sweeps.

What changed

• add jolt-core/src/zkvm/e2e_tests.rs
• move guest/prove/verify e2e tests out of zkvm/prover.rs
• wire the new module from zkvm/mod.rs
• keep prover-internal, security, and BlindFold-specific tests in prover.rs
• expose the trusted-advice preprocessing helper with minimal test-only visibility for shared reuse

Tests moved

• fib_e2e_dory
• small_trace_e2e_dory
• sha3_e2e_dory
• sha2_e2e_dory
• sha2_e2e_dory_with_unused_advice
• advice_e2e_dory
• memory_ops_e2e_dory
• btreemap_e2e_dory
• muldiv_e2e_dory
• stdlib_e2e_dory
• fib_e2e_dory_address_major
• advice_e2e_dory_address_major

Tests intentionally kept in prover.rs

These remain in place because they are more tightly coupled to prover internals, tampering/security properties, or BlindFold-specific behavior:

• max_advice_with_small_trace
• advice_opening_point_derives_from_unified_point
• blindfold_r1cs_satisfaction
• truncated_trace
• malicious_trace
• initial_pc_is_constrained_to_entry_point
• blindfold_protocol_e2e

Validation

Ran targeted formatting and test coverage for the refactor.

Examples:

• rustfmt --edition 2021 jolt-core/src/zkvm/prover.rs jolt-core/src/zkvm/mod.rs jolt-core/src/zkvm/e2e_tests.rs
• cargo nextest run -p jolt-core ... --features host
• cargo nextest run -p jolt-core ... --features host,zk

Closes #1208