Add durable reviewer sessions

[BXya]

Summary

• add durable session kind reviewer
• support ao spawn --role reviewer with explicit harness and issue binding
• persist/list/restore reviewer sessions and reject PR claiming from non-worker sessions
• update API schema, CLI docs, and targeted tests

Scope

This only extends the existing durable session lifecycle. It does not change the PR review pane, add a reviewer UI lane, modify APL, or change GitHub writeback behavior.

Tests

• go test ./internal/storage/sqlite/...
• go test ./internal/storage/sqlite/... ./internal/httpd/controllers ./internal/cli ./internal/service/session ./internal/adapters/agent/qwen ./internal/integration ./internal/skillassets
• go test ./internal/session_manager -run "TestSpawnReviewerPersistsAndRestoresKind|TestSpawnReviewerDoesNotInheritWorkerOverride"
• npm run api
• npm run frontend:typecheck
• git diff --check

Known not green

• Full go test ./... was not used as the gate because existing Windows/environment failures remain outside this reviewer-session change: auth fixture behavior, polluted PTY registry state, Windows mode bits, CRLF worktree expectations, HTTP port fallback, and path separator assertions.

[BXya]

Fork CI evidence is green on BXya#1 for the same branch/commit line.

Passing checks on the fork PR:

• Go / build-test
• Go / lint
• Go / api-drift
• Frontend / test
• CLI E2E / container
• CLI E2E / native (ubuntu-latest)
• CLI E2E / native (macos-latest)
• CLI E2E / native (windows-latest)
• Prettier / format
• gitleaks / scan

Fork evidence PR: BXya#1

The upstream PR still needs maintainer approval to run workflows on AgentWrapper/agent-orchestrator.