test(FN-2197): reconcile skipped-test inventory and stabilize planning resume coverage

- Add docs/skipped-test-inventory.md with the current intentional skip patterns and rationale across test suites
- Link the skipped-test inventory from docs/README.md for easier discovery
- Record reconciliation of older skip follow-up tasks that are now covered and no longer active backlog
- Stabilize PlanningModeModal conversation-history resume testing by overriding stream behavior in the targeted test case

docs/README.md

@@ -62,6 +62,7 @@ For a full walkthrough (installation, onboarding, first task, and daily workflow
 | [Agent Sandbox Research](./agent-sandboxing-research.md) | Research on agent isolation, capability enforcement, and sandboxing approaches |
 | [Agent Gap Analysis](./agent-paperclip-gap-analysis.md) | Gap analysis for agent Paperclip integration |
 | [Test Audit Report](./test-audit-report.md) | Test coverage and effectiveness audit with recommendations |
+| [Skipped Test Inventory](./skipped-test-inventory.md) | Current intentional test-skip inventory and reconciliation status for older skip follow-ups |
 | [Dashboard Load Performance](./performance/dashboard-load.md) | SQLite index analysis and optimization for dashboard boot path queries |
 
 ## External Resources

docs/skipped-test-inventory.md

@@ -0,0 +1,51 @@
+# Skipped Test Inventory
+
+_Last audited: 2026-04-20 (FN-2197)_
+
+This document tracks intentional skip usage in test suites so stale follow-up backlog items can be retired quickly.
+
+## Current Inventory
+
+Audit command:
+
+```bash
+rg -n "\b(it|test|describe)\.skip\b|\bskipIf\b|\?\s*it\s*:\s*it\.skip" packages --glob "**/*.{test,spec}.{ts,tsx}"
+```
+
+Current results:
+
+1. **Intentional cross-coverage alias**
+   - `packages/engine/src/executor.test.ts`
+   - `it.skip("step-session skill selection covered in step-session-executor.test.ts", ...)`
+   - Rationale: dedicated coverage exists in `step-session-executor.test.ts`; this marker documents ownership.
+
+2. **Environment-gated integration aliases**
+   - `packages/dashboard/src/server-static-assets.test.ts`
+   - `packages/dashboard/src/__tests__/websocket.test.ts`
+   - `packages/dashboard/src/__tests__/server-webhook.test.ts`
+   - Pattern: `loopbackBindingAvailable ? it : it.skip`
+   - Rationale: these integration tests require loopback binding support in the runtime environment.
+
+3. **Build-output-gated checks**
+   - `packages/cli/src/__tests__/bundle-output.test.ts`
+   - `packages/dashboard/app/__tests__/build-output.test.ts`
+   - Pattern: `it.skipIf(...)` / `test.skipIf(...)`
+   - Rationale: assertions are valid only when build artifacts are present.
+
+## Older Follow-up Reconciliation
+
+Previously tracked actionable skip follow-ups are now resolved and should not be treated as open backlog:
+
+- **FN-2085**: wildcard proxy POST body forwarding coverage is active.
+- **FN-2076 / FN-2106 / FN-2109**: NewAgentDialog and MissionInterviewModal rollback favorite-toggle regressions are active interaction tests.
+
+Searches for those IDs in repository test code and docs now return no active TODO/skip markers tied to unresolved work.
+
+## Policy
+
+When adding a new skip marker, include one of the following:
+
+- a clear environment/build gate explanation, or
+- a direct reference to the active test that owns equivalent coverage.
+
+Avoid opening follow-up tasks for intentional gate/alias skips unless behavior coverage is actually missing.