fix(git): fix 17 missing async/await bugs + UX overhaul

Backend:
- fix 17 missing 'await' in git route handlers causing silent no-ops
  (branches, diff, history, commit, push, pull, merge, promote, sync)
- fix async coroutine passed to run_blocking in git_plugin.py

Frontend:
- add collapsible 'How it works' onboarding (GitHelpPanel)
- add status legend with color-coded repository statuses
- i18n: add 50+ missing keys, replace hardcoded strings
- add Refresh button in modal header
- add PROD deploy confirmation dialog (replaces browser prompt())
- add CommitHistory to workspace tab with timeline nodes
- add post-commit success banner with next-step guidance
- increase success toast duration to 8s
- group local/remote branches in selector (optgroup)
- format last_modified dates timezone-aware
- change PROD badge from red to neutral indigo
- extract shared resolveGitStatusToken to git-utils.ts
- fix 'slug' label regression
- remove dead init_repo_button key

UI/UX audit fixes:
- add descriptions to Create/Init buttons in init panel
- add actionable CTA to server mismatch warning
- improve checkbox text phrasing

.opencode/agents/security-auditor.md

@@ -13,7 +13,6 @@ permission:
     fullstack-coder: deny
     reflection-agent: deny
     security-auditor: allow
-  steps: 80
 color: warning
 ---
 MANDATORY USE `skill({name="semantics-core"})`, `skill({name="semantics-contracts"})`, `skill({name="molecular-cot-logging"})`, `skill({name="semantics-python"})`, `skill({name="semantics-svelte"})`