Show a real context-usage breakdown (/context) and reflect the always-sent baseline in the indicator

What feature would you like to see?

Two related gaps in how Kimi Code reports context usage:

1. The status-bar indicator under-reports. On a fresh session it shows context: 0.0% (0/262.0k) even though every request already carries a large always-sent baseline — the system prompt, tool schemas, MCP tools, skills listing, and memory (AGENTS.md). The number only becomes meaningful after the first turn, and there is no way to see what fills the window.

2. There is no /context command. Claude Code has a /context command that breaks usage down by category (system prompt, system tools, MCP tools, custom agents, memory files, skills, messages, free space). Kimi Code has /usage (totals + quotas) but nothing that shows the per-category composition.

Proposal

• Add a /context slash command that prints a category breakdown with token counts, percentages, and a progress bar, reusing the existing /usage panel style.
• Add a [context_window] baseline_mode config (off / include / subtract) so users can choose whether the status-bar indicator (and /usage / /status) folds in the baseline. Default off preserves current behavior.

I'm happy to open a PR — I already have an implementation with tests and bilingual docs ready, pending maintainer direction on the approach (especially the default baseline_mode and the three-mode design).

Additional information

• The breakdown is computed in agent-core and surfaced through a new getContextBreakdown() SDK session method (mirrors the existing getUsage / getTools RPC path).
• To avoid double-counting, the /context total is anchored to the model's real reported input-token count after the first turn, so it matches the footer rather than drifting on the character-based estimate.

Start with the existing /usage and /status panels, the agent-core breakdown, and the getUsage/getTools RPC path; use the proposed getContextBreakdown() session method as the entry point. Done means /context reports category counts, percentages, and progress, while the indicator and usage views consistently apply the selected baseline_mode; verify the documented tests and bilingual docs mentioned in the issue.