linear-cli 0.1.2

Bug-fix release. No code-behavior changes; resolves two HN-readiness inconsistencies.

Fixed

• install.sh error message claimed Python 3.10+ was required; the script works on 3.9+ (matches README, badge, comparison table, FAQ).
• SECURITY.md claimed environment variables were rejected as a key-resolution path; the CLI has supported them since 0.1.0 alongside macOS Keychain. Rewrote the section to document all three paths (config / env / Keychain) with explicit tradeoffs.

Demo assets (gif, mp4) remain on v0.1.0.