Add post-4.0 chat product roadmap

Extend the chat ergonomics roadmap now that the core workspace and MCP path are in place for the narrowed chat-host persona.

Add the next planned phase around project-aware chat startup, host bootstrap and repair, reviewable agent output, opinionated use-case modes, and faster daily loops so the roadmap keeps pushing toward a repo-aware daily tool instead of a generic VM or SDK story.

Document the constraints explicitly: optimize the MCP/chat-host path first, keep disk tools secondary, and take advantage of the current no-users-yet window to make breaking product-shaping changes when needed.

docs/roadmap/llm-chat-ergonomics/4.3.0-reviewable-agent-output.md

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+# `4.3.0` Reviewable Agent Output
+
+Status: Planned
+
+## Goal
+
+Make it easy for a human to review what the agent actually did inside the
+sandbox without manually reconstructing the session from diffs, logs, and raw
+artifacts.
+
+## Public API Changes
+
+The product should expose a concise workspace review surface, for example:
+
+- `pyro workspace summary WORKSPACE_ID`
+- `workspace_summary` on the MCP side
+- structured JSON plus a short human-readable summary view
+
+The summary should cover the things a chat-host user cares about:
+
+- commands run
+- files changed
+- diff or patch summary
+- services started
+- artifacts exported
+- final workspace outcome
+
+## Implementation Boundaries
+
+- prefer concise review surfaces over raw event firehoses
+- keep raw logs, diffs, and exported files available as drill-down tools
+- summarize only the sandbox activity the product can actually observe
+- make the summary good enough to paste into a chat, bug report, or PR comment
+
+## Non-Goals
+
+- no full compliance or audit product
+- no attempt to summarize the model's hidden reasoning
+- no remote storage backend for session history
+
+## Acceptance Scenarios
+
+- after a repro-fix or review-eval run, a user can inspect one summary and
+  understand what changed and what to review next
+- the summary is useful enough to accompany exported patches or artifacts
+- unsafe-inspection and review-eval flows become easier to trust because the
+  user can review agent-visible actions in one place
+
+## Required Repo Updates
+
+- public contract, help text, README, and recipe docs updated with the new
+  summary path
+- at least one host-facing example showing how to ask for or export the summary
+- at least one real smoke scenario validating the review surface end to end