feat(skills): add list, find, add, update CLI commands

[amirulabu]

Summary

Adds four new wukong skills subcommands for interacting with the skills registry:

CRF-1140 — wukong skills list

• Fetches full skill catalog from skills GraphQL query
• Displays a table with Name, Slug, Description, and Installed status
• Local-only skills (created via init, not from registry) shown in a separate section
• Installed column shows scope: ✓ project, ✓ global, local, or —

CRF-1141 — wukong skills find <keyword>

• Calls skills query with keyword filter
• Same table format as list, filtered to matching results
• Helpful message when no matches found

CRF-1142 — wukong skills add [name]

• Optional --global / --project flags to skip scope prompt
• If <name> provided and exactly 1 match, auto-selects with confirmation
• If multiple matches or no name, shows inquire::MultiSelect
• Downloads SKILL.md content via skill query, creates .agents/skills/<slug>/SKILL.md + symlink
• Tracks content hashes in mv-manifest.json for future update checks
• Skips already-installed skills with a warning

CRF-1143 — wukong skills update

• Scans project and global mv-manifest.json files for tracked skills
• Calls checkSkillUpdates API with all (slug, currentHash) pairs
• Downloads and replaces SKILL.md for UPDATE_AVAILABLE skills
• Updates manifest hashes; reports updated/up-to-date/not-found counts

SDK Changes

• 3 new GraphQL query files: skills.graphql, skill.graphql, check_skill_updates.graphql
• Updated schema.json with Skill, SkillContent, SkillUpdateState, SkillUpdateStatus, SkillUpdateCheckInput types and query fields
• Added SkillsList, SkillBySlug, CheckSkillUpdates derive structs in skill.rs
• Added fetch_skills(), fetch_skill(), check_skill_updates() to SDK WKClient
• Added CLI-level wrappers with token refresh in wukong_client.rs

Other

• Added CLAUDE.md with pre-commit checks (cargo fmt, cargo clippy, cargo test)

Jira

• CRF-1140
• CRF-1141
• CRF-1142
• CRF-1143

[amirulabu]

Manual Test Run

Tested on macOS with cargo run -p wukong against the dev registry.

# Login
❯ cargo run -p wukong -- login
❯ Choose the account you would like to continue with amirul.a@mindvalley.com
You are logged in as: amirul.a@mindvalley.com

# List skills
➜ cargo run -p wukong -- skills list
┌──────────────┬──────────────┬─────────────┬───────────┐
│ Name         │ Slug         │ Description │ Installed │
├──────────────┼──────────────┼─────────────┼───────────┤
│ hello-world  │ hello-world  │ Test skill  │ —         │
├──────────────┼──────────────┼─────────────┼───────────┤
│ hello-world2 │ hello-world2 │ Test skill  │ —         │
├──────────────┼──────────────┼─────────────┼───────────┤
│ hello-world3 │ hello-world3 │ Test skill3 │ —         │
└──────────────┴──────────────┴─────────────┴───────────┘
# (+ 20 local skills listed correctly)

# Find skill
➜ cargo run -p wukong -- skills find "hello 3"
┌──────────────┬──────────────┬─────────────┬───────────┐
│ Name         │ Slug         │ Description │ Installed │
├──────────────┼──────────────┼─────────────┼───────────┤
│ hello-world3 │ hello-world3 │ Test skill3 │ —         │
└──────────────┴──────────────┴─────────────┴───────────┘

# Add skill
➜ cargo run -p wukong -- skills add hello-world2
❯ Found one skill: hello-world2 — hello-world2. Install it? Yes
❯ Where should these skills be installed? Project (current directory)
  Installed [project] hello-world2

Installed 1 skill(s).

# Update (already up to date)
➜ cargo run -p wukong -- skills update
0 skill(s) updated
  Up to date: hello-world2

All commands working as expected. ✅