Improve Chapter 01 software installation lesson

[jules-tth]

Summary

• Replace the placeholder software installation sublesson with an operator-focused package-management guide.
• Cover trusted package sources, search/inspection flow, install/remove safety, verification, outside repositories, language package managers, containers, and install notes.
• Add a focused lab and review questions around installing and verifying jq.

Verification

• python3 -m mkdocs build --strict
• git diff --check
• find docs -type f -name "*.md" -size 0 -print
• make build

Duplicate check

• Final open-PR file-overlap check for docs/lessons/01_where_to_start/1.10_ways_to_find_and_install_software.md returned no matches immediately before PR creation.