minicon-srcmgr 0.0.3

Source-only release. No binary is attached: signing and six-cell platform evidence are not available yet.

What changed since 0.0.2:

• Panels follow lazygit's numbers: 1 Status, 2 Files, 3 Branches, 4 Commits.
• Main-panel cursor with line-level staging (Space, v for a range) and hunk staging (a).
• a on Files toggles stage-all and unstage-all.
• d on Branches asks before git branch -d; y deletes, n keeps.
• <, >, Home, End, PgUp/PgDn, Ctrl+U and Ctrl+D move through lists and the diff.
• The window redraws on resize and responds to the mouse (clicks and wheel).

Checks: cargo test --workspace (154 passing), clippy with no warnings, docs check PASS, and live window runs.

Details: PRD 12 "Release 0.0.3 status" and PRD 14 "Release 0.0.3 plan" in the repository.