CLI/server report emission + LSP timeout robustness

[mikemol]

Summary

CLI/server emit flags should reliably produce reports/artifacts without LSP timeouts or ambiguous exit behavior.

Scope

• CLI payload plumbing for emit flags.
• Server emit paths for reports/artifacts.
• LSP timeout handling robustness.
• Tests for emit flags + server edges.

Files (expected)

• src/gabion/cli.py
• src/gabion/server.py
• src/gabion/lsp_client.py
• tests/test_cli_payloads.py
• tests/test_server_execute_command_edges.py

Acceptance Criteria

• Emit flags produce expected out/ + artifacts/out outputs.
• LSP timeout behavior is bounded & deterministic.
• Tests cover CLI/server report emission edges.