Fix pytest-socket SocketBlockedError in test_init_setup_entry.py

[dsackr]

Summary

• docs/TEST_LEDGER.md has shown backend-pytest red on main for several days now, always on the same single test: tests/python/setup/test_init_setup_entry.py::test_late_bound_tracker_watch_does_not_violate_thread_safety (pytest_socket.SocketBlockedError).
• Root cause: manifest.json declares dhcp as a dependency, so every hass fixture in this test file also loads HA core's dhcp component. That component's own EVENT_HOMEASSISTANT_STARTED listener calls aiodhcpwatcher.async_init() and (via DHCPWatcher.async_start) aiodhcpwatcher.async_start(), both of which open a real AF_NETLINK socket via scapy — fatal under pytest-socket's sandbox, and unrelated to what this test file actually verifies (this integration's own late-bound tracker-watch listener).
• Fix: stub both aiodhcpwatcher entry points in the file's existing _no_real_network autouse fixture, so firing EVENT_HOMEASSISTANT_STARTED in tests only exercises this integration's own listener, not HA core's real DHCP watcher.

Pure test-infrastructure fix — no product code changed, no behavior change, so no KPF update needed per AGENTS.md.

Note: after this fix, the suite still shows 2 unrelated failures (test_built_in_skills_seeded_on_first_load, test_built_ins_not_reseeded_after_user_deletes_one — a hardcoded built-in-skill count gone stale after the new "Daily Newspaper" skill was added). Out of scope for this PR; left untouched.

Test plan

• tests/python/setup/test_init_setup_entry.py — 9 passed, 0 errors (was: 1 error)
• Full suite — 548 passed, 2 failed (pre-existing, unrelated), 0 errors (was: 1 error)

Co-Authored-By: Claude Sonnet 5 noreply@anthropic.com
Claude-Session: https://claude.ai/code/session_01KmCpFs3Y4KhAjap7dSMNco

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Generated by Claude Code

[dsackr]

CI confirms the fix: 2 failed, 548 passed — the DHCP/scapy SocketBlockedError is gone (0 errors, matching local verification). The 2 remaining failures are the pre-existing, unrelated test_built_in_skills_seeded_on_first_load / test_built_ins_not_reseeded_after_user_deletes_one regression from the "Daily Newspaper" skill addition (already noted in the PR description) — out of scope here. This PR is ready for review/merge whenever convenient.

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Generated by Claude Code