feat(skiff): align CLI with Vercel skills and fix entry symlink

Replace install/uninstall with add/remove, add publish for git ops in
~/.skills, and resolve bin/skiff symlinks so commands work from any cwd.

Co-authored-by: Cursor <cursoragent@cursor.com>

skiff/skills.py

@@ -2,6 +2,7 @@
 
 from __future__ import annotations
 
+import re
 from pathlib import Path
 
 from skiff.paths import SKILLS_DIR, TEMPLATE_DIR, ensure_skills_home
@@ -53,6 +54,45 @@ def resolve_skill_source(name: str, *, source: str | None = None) -> tuple[Path,
     raise SystemExit(f"找不到 skill: {name}")
 
 
+def read_skill_meta(skill_dir: Path) -> dict[str, str]:
+    skill_md = skill_dir / "SKILL.md"
+    if not skill_md.is_file():
+        return {}
+    text = skill_md.read_text(encoding="utf-8")
+    if not text.startswith("---"):
+        return {}
+    end = text.find("\n---", 3)
+    if end == -1:
+        return {}
+    frontmatter = text[3:end]
+    meta: dict[str, str] = {}
+
+    name_match = re.search(r"^name:\s*(.+)$", frontmatter, re.MULTILINE)
+    if name_match:
+        meta["name"] = name_match.group(1).strip().strip("\"'")
+
+    desc_match = re.search(
+        r"^description:\s*(?:>-|>\||>|-)?\s*\n((?:[ \t].+\n?)+)",
+        frontmatter,
+        re.MULTILINE,
+    )
+    if desc_match:
+        lines = [line.strip() for line in desc_match.group(1).splitlines() if line.strip()]
+        meta["description"] = " ".join(lines)
+    else:
+        inline = re.search(r"^description:\s*(.+)$", frontmatter, re.MULTILINE)
+        if inline:
+            meta["description"] = inline.group(1).strip().strip("\"'")
+
+    return meta
+
+
+def skill_description(name: str) -> str | None:
+    meta = read_skill_meta(SKILLS_DIR / name)
+    desc = meta.get("description")
+    return desc.strip() if desc else None
+
+
 def validate_skill_name(name: str) -> None:
     import re