fix(cli): align TUI input and transcript flow

[CxHsin]

Summary

Fixes #3361

Align the TUI input with the terminal edge, add a consistent one-cell gutter around transcript entries, and trim trailing blank rows before applying the transcript separator. This keeps tool stacks evenly spaced after assistant Markdown ends with a blank paragraph.

Verification

• node --test packages/cli/dist/__tests__/pi-transcript.test.js
• npx biome check packages/cli/src/pi-transcript.ts packages/cli/src/pi-tui-runner.ts packages/cli/src/__tests__/pi-transcript.test.ts
• npm --workspace maka-agent test ran the full CLI suite. The new transcript regression passed; 8 pre-existing Windows-environment failures remain: two SIGTERM expectations and six Runtime Host service cases blocked by fsync/symlink permissions.

AI use

• No generative tool made a substantive contribution
• Generative tooling made a substantive contribution

Tool(s) and scope: Codex (GPT-5) implemented the focused TUI layout and transcript-spacing changes, added the regression test, and ran verification. The commit includes Generated-by: Codex (GPT-5).

Checklist

• Tests cover the change and fail without it
• Lint, format, typecheck and the affected suites pass locally

Does this PR entail a change in behavior?

• Yes — described under Summary above
• No

Screenshots

Before

After

[Astro-Han]

LGTM.

[Astro-Han]

The fix is nice and clean. Could we have a before after compirison graph in the PR body?

[CxHsin]

before：

after：