fix(mcp): pass zlob through nested CI cargo runs

[AlexMikhalev]

Summary

• propagate --features zlob to all nested MCP test harness cargo run / cargo build invocations when CI=true
• cover the remaining MCP test files that were still spawning nested builds without the fff-search feature contract
• remove the last deterministic CI Main Branch release-build failures on current main

Verification

• cargo fmt
• CI=true cargo test --release --target x86_64-unknown-linux-gnu -p terraphim_mcp_server --test integration_test --features zlob -- --nocapture
• CI=true cargo test --release --target x86_64-unknown-linux-gnu -p terraphim_mcp_server --test mcp_autocomplete_e2e_test --features zlob -- --nocapture
• CI=true cargo test --release --target x86_64-unknown-linux-gnu -p terraphim_mcp_server --test test_mcp_fixes_validation --features zlob -- --nocapture
• CI=true cargo test --release --target x86_64-unknown-linux-gnu --workspace --features "self_update/signatures,zlob"