chore(01): resume work — consume HANDOFF.json + ignore dist-archives

- Delete .planning/HANDOFF.json (one-shot artifact per resume-project workflow)
- Add dist-archives/ to .gitignore (from prior session's distribution-zip build)
- Bump STATE.md Session Continuity to reflect resumed session + next action
  (install-flow + auto-select researcher spawn)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitignore

@@ -4,4 +4,6 @@ dist-test/
 *.log
 .DS_Store
 .vscode/
-.idea/
+.idea/
+# distribution artifacts (release zips; produced via build pipeline)
+dist-archives/