fix(setup): install missing Matrix E2EE companion deps

[LeonSGP43]

Summary

• install the missing platform.matrix package specs during setup wizard E2EE flows instead of only installing mautrix[encryption]
• keep the non-E2EE path unchanged while improving the manual recovery hint for failed E2EE installs
• add a setup regression test that proves a missing companion dependency like asyncpg is included in the install command

Testing

• /Users/leongong/Desktop/LeonProjects/worktrees/hermes-agent/.base/.venv/bin/python -m pytest -q -o addopts='' tests/hermes_cli/test_setup_matrix_e2ee.py
• source /Users/leongong/Desktop/LeonProjects/worktrees/hermes-agent/.base/.venv/bin/activate && python -m ruff check hermes_cli/setup.py tests/hermes_cli/test_setup_matrix_e2ee.py
• git diff --check

Closes #31116.

[alt-glitch]

Subset of #31236, which fixes both the Matrix E2EE missing deps and the Discord auto-enable issue from #31116. This PR only addresses the E2EE deps portion.

[teknium1]

This looks implemented on current main; closing as superseded by the merged fix. This is an automated hermes-sweeper review.

Evidence:

• hermes_cli/setup.py:1957 now routes the Matrix E2EE setup path through the central lazy-deps feature group and calls _lazy_ensure("platform.matrix", prompt=False) instead of only installing mautrix[encryption].
• tools/lazy_deps.py:136 defines platform.matrix with the companion dependencies this PR was adding: mautrix[encryption], aiosqlite, asyncpg, and aiohttp-socks.
• The implementation is from 54e61f93318d579b145421c447437ec345021eb1 (fix(matrix,gateway): Matrix E2EE installs full dep set; plugins respect is_connected), which is contained in release tag v2026.5.28.
• The existing maintainer discussion also identifies this PR as the E2EE-deps subset of fix(gateway+setup): repair Matrix E2EE deps and stop Discord auto-enable on fresh installs (#31116) #31236, whose fix landed via that same commit.