Update README.MD and add nano-claude-code v3.0 + original-source-code/src

- README.MD: add original-source-code and nano-claude-code sections, update
  overview table (4 subprojects), add v3.0 news entry, expand comparison table
  with memory/multi-agent/skills dimensions
- nano-claude-code v3.0: multi-agent package (multi_agent/), memory package
  (memory/), skill package (skill/) with built-in /commit and /review skills,
  context compression (compaction.py), tool registry plugin system, diff view,
  17 slash commands, 18 built-in tools, 101 tests (~5000 lines total)
- original-source-code/src: add raw TypeScript source tree (1884 files)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

nano-claude-code/skill/loader.py

@@ -0,0 +1,184 @@
+"""Skill loading: parse markdown files with YAML frontmatter into SkillDef objects."""
+from __future__ import annotations
+
+from dataclasses import dataclass, field
+from pathlib import Path
+from typing import Optional
+
+
+@dataclass
+class SkillDef:
+    name: str
+    description: str
+    triggers: list[str]          # ["/commit", "commit changes"]
+    tools: list[str]             # ["Bash", "Read"]  (allowed-tools)
+    prompt: str                  # full prompt body after frontmatter
+    file_path: str
+    # Enhanced fields
+    when_to_use: str = ""        # when Claude should auto-invoke this skill
+    argument_hint: str = ""      # e.g. "[branch] [description]"
+    arguments: list[str] = field(default_factory=list)  # named arg names
+    model: str = ""              # model override
+    user_invocable: bool = True  # appears in /skills list
+    context: str = "inline"      # "inline" or "fork" (fork = sub-agent)
+    source: str = "user"         # "user", "project", "builtin"
+
+
+# ── Directory paths ────────────────────────────────────────────────────────
+
+def _get_skill_paths() -> list[Path]:
+    return [
+        Path.cwd() / ".nano_claude" / "skills",   # project-level (priority)
+        Path.home() / ".nano_claude" / "skills",   # user-level
+    ]
+
+
+# ── List field parser ──────────────────────────────────────────────────────
+
+def _parse_list_field(value: str) -> list[str]:
+    """Parse YAML-like list: ``[a, b, c]`` or ``"a, b, c"``."""
+    value = value.strip()
+    if value.startswith("[") and value.endswith("]"):
+        value = value[1:-1]
+    return [item.strip().strip('"').strip("'") for item in value.split(",") if item.strip()]
+
+
+# ── Single-file parser ─────────────────────────────────────────────────────
+
+def _parse_skill_file(path: Path, source: str = "user") -> Optional[SkillDef]:
+    """Parse a markdown file with ``---`` frontmatter into a SkillDef.
+
+    Frontmatter fields:
+        name, description, triggers, tools / allowed-tools,
+        when_to_use, argument-hint, arguments, model,
+        user-invocable, context
+    """
+    try:
+        text = path.read_text(encoding="utf-8")
+    except Exception:
+        return None
+
+    if not text.startswith("---"):
+        return None
+
+    parts = text.split("---", 2)
+    if len(parts) < 3:
+        return None
+
+    frontmatter_raw = parts[1].strip()
+    prompt = parts[2].strip()
+
+    fields: dict[str, str] = {}
+    for line in frontmatter_raw.splitlines():
+        line = line.strip()
+        if not line or ":" not in line:
+            continue
+        key, _, val = line.partition(":")
+        fields[key.strip().lower()] = val.strip()
+
+    name = fields.get("name", "")
+    if not name:
+        return None
+
+    # allowed-tools wins over tools if present
+    tools_raw = fields.get("allowed-tools", fields.get("tools", ""))
+    tools = _parse_list_field(tools_raw) if tools_raw else []
+
+    triggers_raw = fields.get("triggers", "")
+    triggers = _parse_list_field(triggers_raw) if triggers_raw else [f"/{name}"]
+
+    arguments_raw = fields.get("arguments", "")
+    arguments = _parse_list_field(arguments_raw) if arguments_raw else []
+
+    user_invocable_raw = fields.get("user-invocable", "true")
+    user_invocable = user_invocable_raw.lower() not in ("false", "0", "no")
+
+    context = fields.get("context", "inline").strip().lower()
+    if context not in ("inline", "fork"):
+        context = "inline"
+
+    return SkillDef(
+        name=name,
+        description=fields.get("description", ""),
+        triggers=triggers,
+        tools=tools,
+        prompt=prompt,
+        file_path=str(path),
+        when_to_use=fields.get("when_to_use", ""),
+        argument_hint=fields.get("argument-hint", ""),
+        arguments=arguments,
+        model=fields.get("model", ""),
+        user_invocable=user_invocable,
+        context=context,
+        source=source,
+    )
+
+
+# ── Registry of built-in skills (registered by builtin.py) ────────────────
+
+_BUILTIN_SKILLS: list[SkillDef] = []
+
+
+def register_builtin_skill(skill: SkillDef) -> None:
+    _BUILTIN_SKILLS.append(skill)
+
+
+# ── Load all skills ────────────────────────────────────────────────────────
+
+def load_skills(include_builtins: bool = True) -> list[SkillDef]:
+    """Return skills from disk + builtins, deduplicated (project > user > builtin)."""
+    seen: dict[str, SkillDef] = {}
+
+    # Builtins go in first (lowest priority)
+    if include_builtins:
+        for sk in _BUILTIN_SKILLS:
+            seen[sk.name] = sk
+
+    # User-level next, project-level last (highest priority)
+    skill_paths = _get_skill_paths()
+    for i, skill_dir in enumerate(reversed(skill_paths)):
+        src = "user" if i == 0 else "project"
+        if not skill_dir.is_dir():
+            continue
+        for md_file in sorted(skill_dir.glob("*.md")):
+            skill = _parse_skill_file(md_file, source=src)
+            if skill:
+                seen[skill.name] = skill
+
+    return list(seen.values())
+
+
+def find_skill(query: str) -> Optional[SkillDef]:
+    """Find a skill whose trigger matches the first word (or whole string) of query."""
+    query = query.strip()
+    if not query:
+        return None
+
+    first_word = query.split()[0]
+    for skill in load_skills():
+        for trigger in skill.triggers:
+            if first_word == trigger:
+                return skill
+            if trigger.startswith(first_word + " "):
+                return skill
+    return None
+
+
+# ── Argument substitution ─────────────────────────────────────────────────
+
+def substitute_arguments(prompt: str, args: str, arg_names: list[str]) -> str:
+    """Replace $ARGUMENTS (whole args string) and $ARG_NAME placeholders.
+
+    Named args are positional: first word → first name, etc.
+    """
+    # Always substitute $ARGUMENTS
+    result = prompt.replace("$ARGUMENTS", args)
+
+    # Named args: split by whitespace
+    arg_values = args.split()
+    for i, arg_name in enumerate(arg_names):
+        placeholder = f"${arg_name.upper()}"
+        value = arg_values[i] if i < len(arg_values) else ""
+        result = result.replace(placeholder, value)
+
+    return result