[feat] Workflow panel — detect + inventory view (read-only)

[Sph3ricalPeter]

Priority: Low — convenience / inspector, not a core-thesis feature (see direction discussion)
Effort: ~1–2 days
Engine: None — pure detection + presentation of harness-native files
Part of: the v2.1.0 agentic-workflow surfaces

Read-only "Workflow" surface: detect the repo's agent-config artifacts and render them grouped by type. No editing — the IDE / Claude Code is the better editor; this is a glance / inspector, deliberately not an authoring tool.

Detect (harness-native, no engine)

• Instruction files: CLAUDE.md, .claude/CLAUDE.md, CLAUDE.local.md, AGENTS.md; ancestor / monorepo CLAUDE.md up the tree.
• Skills: .claude/skills/*, .codex/skills/* (name + description from frontmatter).
• Rules: .claude/rules/**/*.md — surface each rule's paths: frontmatter (the scope).
• Hooks: events + commands from .claude/settings.json (+ settings.local.json).
• MCP servers: .mcp.json / settings (name, transport, scope).
• Optional, read-only if present: .aw/manifest.toml.

View (Inventory)

• Sidebar WORKFLOW section (sibling to Branches / CI) with per-type counts; appears only when artifacts are detected; clean empty state otherwise.
• Main panel groups detected units by type; each row shows the standout metadata: rule paths: scopes, harness, MCP scope, and a budget flag on any CLAUDE.md over ~200 lines (the adherence cliff).
• Selecting an item opens it read-only (reuse existing viewer).

Out of scope (explicit)

• Editing / scaffolding / toggling — the IDE owns authoring (decided 2026-06-20).
• Any layer-resolution / composition engine.
• The pipeline (lifecycle) view — separate issue.

Acceptance criteria

• Detects all listed artifact types across Claude Code + Codex layouts
• WORKFLOW sidebar section with counts; hidden when none present; clean empty state
• Inventory groups by type; rule rows show paths: scope; CLAUDE.md >200 lines flagged
• Read-only — no write paths introduced
• Detection is cheap (no watch storms); refresh on focus / explicit action