[Feature Request] Unified Plan pane aggregating Plan Mode, TaskList, spec documents, and chat plans

Bug Description
Plan pane — opportunity for a unified planning surface In Claude Code today there are four parallel planning surfaces and none of them know about each other: the Plan pane (populated only in Plan Mode), the TaskList tracker (via TaskCreate), structured spec documents on disk (Kiro-style .kiro/specs/* markdown in our case, but any planning markdown applies) and free-form multi-step plans the agent writes inline in chat. As a user I have to context-switch between all four to understand where the work stands, and the chat plans scroll away the moment the agent starts executing. The Plan pane sits empty for most of a session because the threshold to populate it (entering Plan Mode explicitly) doesn't match how plans actually get authored in practice. A higher-leverage shape would be a single Plan pane that ingests from every source and tags the source on each entry: plan-mode, task:#9, spec:mssql-v3, chat. Even better if entries can link: spec X spawned tasks 9 through 15, task 11 is in_progress, last chat exchange updated the design doc. A small "current plan" pinned area for the working theme, the rest as a scrollable timeline. That turns four siloed surfaces into one place I look to answer "where are we" — a substantial usability win for any non-trivial session.

Environment Info

• Platform: darwin
• Terminal: Apple_Terminal
• Version: 2.1.131
• Feedback ID: 8805e5fc-279a-4182-abca-20eb104c2fde

Errors

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