[beinan]

Summary

Node diagnostics currently expose disk admission but cannot show whether runtime requests are rejected by request slots or byte capacity. Include the existing bounded admission observations in node status and readiness responses for data, control, incoming peers, and outgoing peers. The values are sampled independently, exclude transport budgets, and do not change readiness decisions.

Refs #378. Built on merged #451 and #460.

Testing

• Formatting and service-feature Clippy passed.
• All three node-service tests passed, including six actual replica processes across two groups, snapshot catch-up, leader termination, and restart.
• The real-quorum publisher admission regression passed: byte pressure, request pressure, and credit release remain distinguishable.
• The same feature also passed a three-process release smoke check with separately configured control budgets before promotion onto main.
• Repository CI-equivalent checks passed: workspace Rust tests, formatting, Clippy, Python tests, Ruff, and Pyright. Nine Python fixtures initially could not find the server in the shared-target build environment; all nine passed after building and placing the correct executable. Final-commit CI is still required before merge.