feat: add MiniMax Code support

[hetaoBackend]

Summary

• add MiniMax Code (mcode) as a first-class command preset and state-detection strategy
• detect active turns and pending permission/questionnaire decisions from MCode's stable TUI status markers
• pass preset prompts as MCode's final positional argument and document installation

The detector deliberately avoids generic transcript words such as thinking, so completed assistant output cannot keep a session falsely busy.

Verification

• bunx vitest run src/services/stateDetector/mcode.test.ts src/utils/presetPrompt.test.ts (38 passed)
• bun run typecheck
• bun run lint
• bun run build
• real MCode v0.1.2 PTY screen inspected for the published ● Ready footer

bun run test reaches 896 passing / 5 skipped tests locally, with 12 unrelated Unicode-spinner failures. The same 12 failures reproduce unchanged on origin/main in terminalCapabilities.test.ts and LoadingSpinner.test.tsx in this environment.

AI assistance

This contribution was implemented with AI assistance. The status markers and prompt contract were verified against the MiniMax Code source and a real local PTY session; all submitted code and tests were reviewed before opening this PR.

[kbwo]

Thank you!