refactor: cleanup submodules and add depth support (#99)

* chore: remove vendor and source submodules

Remove submodules that are no longer needed:
- sources/* (vue, nuxt, vite, unocss, pnpm, pinia, vitest, vitepress)
- vendor/antfu-skills, vendor/nuxt-ui, vendor/mastra, vendor/prisma,
  vendor/slidev, vendor/supabase, vendor/vuejs-ai, vendor/vueuse

* chore: remove vendor-synced skills and update plugin manifests

Remove skills that were synced from removed vendor submodules.
Update plugin.json files that referenced removed skills.

* feat(scripts): add shallow clone depth support for submodules

Add depth option to SubmoduleMeta, VendorMeta, and ExtensionMeta
interfaces. Pass --depth flag to git submodule add/update commands.
Set shallow=true in .gitmodules for depth-enabled submodules.

* feat(plugins): migrate all vendor/source skills to skills.sh

Replace Type 1 (sources/) and Type 2 (vendor/) submodule-based skill
sync with skills.sh-managed skills for all plugins.

Migrated plugins:
- Type 1 (sources/ → skills.sh): nuxt, pinia, vite, vitepress, vitest,
  unocss, pnpm, vue
- Type 2 (vendor/ → skills.sh): antfu, slidev, vueuse, vuejs-ai, mastra,
  supabase, prisma, better-auth, agent-browser, ai-sdk, nuxt-ui

Changes:
- Move skills/ → .agents/skills/ for all migrated plugins
- Install skills via `bunx skills add <repo> --skill <name> --agent universal -y`
- Add skills-lock.json and "skills" field to each plugin.json
- Remove 8 sources/ submodules and 11 vendor/ submodules from .gitmodules
- Remove entries from scripts/meta.ts (submodules, vendors, manual)
- Remove entries from scripts/cli.ts (SKILL_TO_PLUGIN, ANTFU_MANUAL_DIR)
- Clean up skills.sh-created agent symlink dirs (.claude, .continue, etc.)
- Remove old SYNC.md and LICENSE.md files

Remaining vendor submodule: web-design-guidelines

* fix(sync): restore verbatimSymlinks option in vendor skill cpSync

The verbatimSymlinks: true option was accidentally dropped from the
vendor skill copy path during the skills.sh migration cleanup.

Author: amondnet

.gitmodules

@@ -28,69 +28,12 @@
 [submodule "external-plugins/open-aware"]
 	path = external-plugins/open-aware
 	url = git@github.com:amondnet/open-aware.git
-[submodule "vendor/antfu-skills"]
-	path = vendor/antfu-skills
-	url = https://github.com/antfu/skills.git
 [submodule "external-plugins/playwright-cli"]
 	path = external-plugins/playwright-cli
 	url = git@github.com:pleaseai/playwright-cli.git
-[submodule "sources/vue"]
-	path = sources/vue
-	url = https://github.com/vuejs/docs
-[submodule "sources/nuxt"]
-	path = sources/nuxt
-	url = https://github.com/nuxt/nuxt
-[submodule "sources/vite"]
-	path = sources/vite
-	url = https://github.com/vitejs/vite
-[submodule "sources/unocss"]
-	path = sources/unocss
-	url = https://github.com/unocss/unocss
-[submodule "sources/pnpm"]
-	path = sources/pnpm
-	url = https://github.com/pnpm/pnpm.io
-[submodule "sources/pinia"]
-	path = sources/pinia
-	url = https://github.com/vuejs/pinia
-[submodule "sources/vitest"]
-	path = sources/vitest
-	url = https://github.com/vitest-dev/vitest
-[submodule "sources/vitepress"]
-	path = sources/vitepress
-	url = https://github.com/vuejs/vitepress
-[submodule "vendor/slidev"]
-	path = vendor/slidev
-	url = https://github.com/slidevjs/slidev
-[submodule "vendor/vueuse"]
-	path = vendor/vueuse
-	url = https://github.com/vueuse/skills
-[submodule "vendor/vuejs-ai"]
-	path = vendor/vuejs-ai
-	url = https://github.com/vuejs-ai/skills
 [submodule "vendor/web-design-guidelines"]
 	path = vendor/web-design-guidelines
 	url = https://github.com/vercel-labs/agent-skills
-[submodule "vendor/mastra"]
-	path = vendor/mastra
-	url = https://github.com/mastra-ai/skills
-[submodule "vendor/nuxt-ui"]
-	path = vendor/nuxt-ui
-	url = https://github.com/nuxt/ui
-[submodule "vendor/supabase"]
-	path = vendor/supabase
-	url = https://github.com/supabase/agent-skills
-[submodule "vendor/prisma"]
-	path = vendor/prisma
-	url = https://github.com/prisma/skills
-[submodule "vendor/better-auth"]
-	path = vendor/better-auth
-	url = https://github.com/better-auth/skills
-[submodule "vendor/agent-browser"]
-	path = vendor/agent-browser
-	url = https://github.com/vercel-labs/agent-browser
-[submodule "vendor/ai-sdk"]
-	path = vendor/ai-sdk
-	url = https://github.com/vercel/ai
 [submodule "external-plugins/google-workspace"]
 	path = external-plugins/google-workspace
 	url = https://github.com/googleworkspace/cli