v2.12.6 — Bulletproof shell aliases

Added

• Bulletproof shell aliases: All aliases now use a _lc wrapper function that silently falls back to the original command if the lean-ctx binary is missing (exit 127) or not executable (exit 126). If lean-ctx is removed, commands like ls, git, grep continue working as if lean-ctx was never installed
• Binary existence guard: Shell hook checks command -v lean-ctx before activating aliases
• Shell config backup: .lean-ctx.bak backup created before every modification
• Panic handler: Human-friendly recovery instructions instead of Rust backtraces
• lean-ctx init --dry-run: Preview changes without modifying anything
• Troubleshooting section in --help and README

Changed

• Shell hook aliases route through _lc wrapper — zero performance difference, full safety net

Full Changelog: v2.12.5...v2.12.6

Full Changelog: v2.12.5...v2.12.6