control-connection: run topology removals through cluster

[dkropachev]

Problem

Node-list reconciliation removes absent host IDs directly from metadata. That bypasses the cluster removal lifecycle, leaving session pools, load-balancing policies, listeners, control-connection state, and metrics associated with the removed host active.

Host-ID reindexing adds two constraints: stale metadata aliases must be removed without tearing down the still-registered Host, and overlapping refreshes must not interleave reindexing with removal lifecycle work.

Fix

Route absent snapshot IDs through a cluster removal entry point that performs lifecycle cleanup without recursively starting another topology refresh. Preserve a Host that remains registered under a new ID, and serialize node-list refreshes so reindexing and stale-ID cleanup cannot overlap.

Fixes #1007

Dependency

This draft is stacked on #1035 for the exact-Host registration helper. #1035 is itself stacked on #1032. Retarget this PR after the preceding drafts merge.

Testing

• TZ=UTC uv run pytest -q tests/unit/test_cluster.py tests/unit/test_control_connection.py — 122 passed
• git diff --check

Pre-review checklist

• I have split my patch into logically separate commits.
• All commit messages clearly explain what they change and why.
• I added relevant tests for new features and bug fixes.
• All commits compile, pass static checks and pass test.
• PR description sums up the changes and reasons why they should be introduced.
• I have provided docstrings for the public items that I want to introduce. (Not applicable: no public items added.)
• I have adjusted the documentation in ./docs/source/. (Not applicable: internal topology lifecycle fix.)
• I added appropriate Fixes: annotations to PR description.

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