Recover the MCP lane on top of current main

This resolves the stale-branch merge against origin/main, keeps the MCP runtime wiring, and preserves prompt-approved CLI tool execution after the mock parity harness additions landed upstream.

Constraint: Branch had to absorb origin/main changes through a contentful merge before more MCP work
Constraint: Prompt-approved runtime tool execution must continue working with new CLI/mock parity coverage
Rejected: Keep permission enforcer attached inside CliToolExecutor for conversation turns | caused prompt-approved bash parity flow to fail as a tool error
Rejected: Defer the merge and continue on stale history | would leave the lane red against current main
Confidence: high
Scope-risk: moderate
Reversibility: clean
Directive: Runtime permission policy and executor-side permission enforcement are separate layers; do not reapply executor enforcement to conversation turns without revalidating mock parity harness approval flows
Tested: cargo test -p rusty-claude-cli --test mock_parity_harness -- --nocapture; cargo test -p rusty-claude-cli -- --nocapture; cargo test --workspace -- --nocapture
Not-tested: Additional live remote/provider scenarios beyond the existing workspace suite

rust/crates/rusty-claude-cli/Cargo.toml

@@ -26,3 +26,8 @@ tools = { path = "../tools" }
 
 [lints]
 workspace = true
+
+[dev-dependencies]
+mock-anthropic-service = { path = "../mock-anthropic-service" }
+serde_json.workspace = true
+tokio = { version = "1", features = ["rt-multi-thread"] }