chore: bump version to 4.3.4, fix skill references after upstream merge

chore(plugin): update Cursor plugin metadata for superpowers-extended…

…-cc rebrand

fix: HARD-GATE on ExitPlanMode + remove disable-model-invocation from…

… commands

- Add <HARD-GATE> at Execution Handoff in writing-plans to prevent
  ExitPlanMode at the decision point (top-of-file constraint insufficient)
- Remove disable-model-invocation from commands/write-plan.md,
  brainstorm.md, execute-plan.md so model can chain skills via commands
- Remove development plan files from repo (upstream's plans preserved)
- Bump version to 4.3.2

chore: bump version to 4.3.1

chore: bump version to 4.2.3

fix(writing-plans): add CRITICAL CONSTRAINTS to prevent ExitPlanMode …

…usage

- Add CRITICAL CONSTRAINTS section at top of SKILL.md prohibiting ExitPlanMode
- Fix TaskCreate description: remove fake placeholder paths, instruct to copy from plan
- Add /test-writing-plans command for compliance testing with Sonnet subagent
- Verified fix works: cross-tested original vs fixed with parallel subagents

chore: bump version to 4.2.1

chore: bump version to 4.1.6

Merge upstream/main (77 commits)

Resolves conflicts:
- plugin.json/marketplace.json: Keep our name/version (superpowers-extended-cc v4.1.4)
- README.md: Keep our fork-specific wording
- RELEASE-NOTES.md: Remove (we use GitHub releases)
- subagent-driven-development: Accept upstream improvements (worktree requirement, main branch warning)
- test-subagent-driven-development.sh: Accept upstream test improvements

chore: bump version to 4.1.4