feat: add 'ready' activity state for live session detection

[AgentWrapper]

Summary

• Adds a new "ready" activity state (🟢) to distinguish sessions that finished their turn and are waiting for input from truly stale sessions
• Sessions where Claude finished responding were shown as "idle" (💤) — indistinguishable from abandoned sessions. Users couldn't tell if ao-38 was alive and ready vs dead.
• ready (🟢) = process alive, finished turn, <5min since last activity
• idle (🟡) = process alive but no activity for >5min (stale/dormant)

Changes

File	Change
packages/core/src/types.ts	Added "ready" to ActivityState union + ACTIVITY_STATE.READY
packages/plugins/agent-claude-code/src/index.ts	Rewrote getActivityState() with ready/idle split at 5min threshold
packages/core/src/session-manager.ts	Fallback on detection error → "ready" (runtime is known alive)
packages/web/src/components/SessionCard.tsx	Added 🟢 ready icon, changed idle to 🟡
packages/cli/src/lib/format.ts	Added cyan "ready" display in CLI
packages/cli/src/commands/status.ts	Map assistant/system → "ready" instead of "idle"
Tests (2 files)	Updated expectations for new semantics

Activity state semantics

State	Icon	Meaning
active	⚡	Processing (thinking, running tools)
ready	🟢	Finished turn, alive, waiting for input (<5min)
idle	🟡	Process alive but stale (>5min)
waiting_input	❓	Permission prompt
blocked	🚧	Error
exited	💀	Process terminated

Test plan

• All 131 core tests pass
• All 138 CLI tests pass
• All plugin tests pass
• Typecheck clean across all 22 packages
• Lint clean (no new issues)
• Build succeeds including Next.js web package
• Verify ao-38 (alive, waiting) shows 🟢 ready on dashboard
• Verify actively processing sessions show ⚡ active
• Verify old stale sessions show 🟡 idle
• Verify killed sessions show 💀 exited

🤖 Generated with Claude Code

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

SessionDetail missing "ready" in activity label map

Medium Severity

The new "ready" activity state is added to SessionCard.tsx's activityIcon map but not to SessionDetail.tsx's activityLabel map (line 20–26 of that file). Sessions in the "ready" state — now the most common state for finished-turn sessions — will fall through to the fallback, displaying a raw lowercase "ready" string in muted gray instead of a properly formatted "Ready" label with a distinct color. This defeats the purpose of the feature in the detail view.

Additional Locations (1)

• packages/core/src/types.ts#L46-L47