Add v0.6.0: full skill/agent QA pass, 3 new agents tested, template cleanup

Skills fixed: sprint-status (stale escalation, threshold), retrospective
(existing file detection, missing data fallback), changelog (misc category,
task-ref count), patch-notes (BLOCKED on missing changelog, tone/template
paths), story-readiness (Phase 0 mode resolution, QL-STORY-READY gate),
art-bible, brainstorm, design-system, ux-design, dev-story, story-done,
create-architecture, create-control-manifest, map-systems, propagate-design-change,
quick-design, prototype, asset-spec.

Agents fixed: all 4 directors (gate verdict token format), engine-programmer,
ui-programmer, tools-programmer, technical-artist (engine version safety),
gameplay-programmer (ADR compliance), godot-gdextension-specialist (ABI warning),
systems-designer (escalation path to creative-director), accessibility-specialist
(model, tools, WCAG criterion format, findings template), live-ops-designer
(escalation paths, battle pass value language), qa-tester (model, test case
format, evidence routing, ambiguous criteria, regression scope).

Specs updated: smoke-check and adopt specs rewritten to match actual skill
behavior. catalog.yaml reset to blank template state. Removed
session-state marketing research file, removed session-state from gitignore.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.claude/skills/story-done/SKILL.md

@@ -418,3 +418,11 @@ If no more stories are ready but Must Have stories are still In Progress (not Co
   anyway; document the risk explicitly if they do.
 - Use `AskUserQuestion` for the code review prompt and for batching manual
   criteria confirmations.
+
+---
+
+## Recommended Next Steps
+
+- Run `/story-readiness [next-story-path]` to validate the next story before starting implementation
+- If all Must Have stories are complete: run `/smoke-check sprint` → `/team-qa sprint` → `/gate-check`
+- If tech debt was logged: track it via `/tech-debt` to keep the register current