Compare inline Agent configuration

Traceability

• Spec ID: compare-inline-agent-configuration
• Status: Implemented
• Supersedes: AC-3 of compare-input-flow
• Request: the Compare configuration panel sits in the wrong place; put it inside the input region's Agent control, on the same model the Memory analysis composer already uses, and keep it as small as possible.

Intent

A chosen Agent and that Agent's configuration are one object, so Compare states them as one control inside the composer rather than as a chip in the toolbar plus a stacked configuration panel below it. Compare and the Memory analysis composer then share one rule: offered settings render compact, in place, inside the input region, and never as a second surface.

Acceptance Scenarios

• AC-1: Choosing an Agent renders one control inside the composer carrying that Agent's name, its offered core settings, and its Remove action. No separate configuration panel, prepare/refresh button, or Ready status is rendered.
• AC-2: The offered settings are the compact AcpSessionSettings toolbar used by the Memory analysis composer, and remaining options open as one pop-up anchored to the composer, above it, bounded at wide, compact, and narrow layouts.
• AC-3: Settings edited in the composer stay per Agent; changing one Agent's model or reasoning effort does not change another's, and a rejected change reverts to the value the Agent still reports.
• AC-4: A preparation failure is recoverable on the Agent it belongs to: that control offers Retry, which re-prepares only that Agent and keeps the already settled Agents and the current prompt.
• AC-5: The composer states a prerequisite only when no Agent row can: no local ACP Agent is available, or no Agent is chosen yet.

Non-goals

Do not change ACP preparation, the launch path, lane rendering after a prompt starts, the Agent catalog or its four-Agent ceiling, the Memory surface, or release metadata. Do not add Agent adapters or invent configuration options.

Plan and Tasks

1. Merge the Agent chip and its configuration section into one composer control and drop the Configure Agents refresh button and the Ready readiness text.
2. Render AcpSessionSettings in compact mode inside that control, grouped per Agent, with the overflow disclosure anchored to the composer.
3. Replace the composer-wide refresh with a per-Agent Retry so one failure cannot discard the Agents that already settled.
4. Remove the superseded configuration-panel styles, labels, and the stale narrow Agent-slot rules; update the English and Chinese labels.
5. Update the browser coverage that asserted the old panel, refresh button, and readiness text.

Test and Review Evidence

• AC-1/AC-2/AC-3: test/browser/acp-session-controls.spec.mjs asserts the Agent controls live inside .live-compare-composer, that no Configure Agents button, readiness text, or transcript exists before the prompt starts, that a 503 config response reverts the model and a retry applies it, and that the second Agent keeps its own value; screenshots at 1440×900, 1024×768, 390×844 verify focus, bounded overflow, and no console/page errors.
• AC-4/AC-5: test/browser/acp-debugger.spec.mjs covers the empty-choice prerequisite, Agent removal by name, and the four-Agent ceiling.
• Verified locally: npm run build, npx vitest run (88 files, 658 tests), and npx playwright test test/browser/acp-session-controls.spec.mjs test/browser/acp-debugger.spec.mjs (10 scenarios) passed.
• Risk: preparation streams still stay live until start or removal; Retry must release the failed Agent's run before starting a replacement.