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/builtin.py

@@ -0,0 +1,100 @@
+"""Built-in skills that ship with nano-claude-code."""
+from __future__ import annotations
+
+from .loader import SkillDef, register_builtin_skill
+
+# ── /commit ────────────────────────────────────────────────────────────────
+
+_COMMIT_PROMPT = """\
+Review the current git state and create a well-structured commit.
+
+## Steps
+
+1. Run `git status` and `git diff --staged` to see what is staged.
+   - If nothing is staged, run `git diff` to see unstaged changes, then stage relevant files.
+2. Analyze the changes:
+   - Summarize the nature of the change (feature, bug fix, refactor, docs, etc.)
+   - Write a concise commit title (≤72 chars) focusing on *why*, not just *what*.
+   - If multiple logical changes exist, ask the user whether to split them.
+3. Create the commit:
+   ```
+   git commit -m "<title>"
+   ```
+   If additional context is needed, add a body separated by a blank line.
+4. Print the commit hash and summary when done.
+
+**Rules:**
+- Never use `--no-verify`.
+- Never commit files that likely contain secrets (.env, credentials, keys).
+- Prefer imperative mood in the title: "Add X", "Fix Y", "Refactor Z".
+
+User context: $ARGUMENTS
+"""
+
+_REVIEW_PROMPT = """\
+Review the code or pull request and provide structured feedback.
+
+## Steps
+
+1. Understand the scope:
+   - If a PR number or URL is given in $ARGUMENTS, use `gh pr view $ARGUMENTS --patch` to get the diff.
+   - Otherwise, use `git diff main...HEAD` (or `git diff HEAD~1`) for local changes.
+2. Analyze the diff:
+   - Correctness: Are there bugs, edge cases, or logic errors?
+   - Security: Injection, auth issues, exposed secrets, unsafe operations?
+   - Performance: N+1 queries, unnecessary allocations, blocking calls?
+   - Style: Does it follow existing conventions in the codebase?
+   - Tests: Are new behaviors tested? Do existing tests cover the change?
+3. Write a structured review:
+   ```
+   ## Summary
+   One-line overview of what the change does.
+
+   ## Issues
+   - [CRITICAL/MAJOR/MINOR] Description and location
+
+   ## Suggestions
+   - Nice-to-have improvements
+
+   ## Verdict
+   APPROVE / REQUEST CHANGES / COMMENT
+   ```
+4. If changes are needed, list specific file:line references.
+
+User context: $ARGUMENTS
+"""
+
+
+def _register_builtins() -> None:
+    register_builtin_skill(SkillDef(
+        name="commit",
+        description="Review staged changes and create a well-structured git commit",
+        triggers=["/commit"],
+        tools=["Bash", "Read"],
+        prompt=_COMMIT_PROMPT,
+        file_path="<builtin>",
+        when_to_use="Use when the user wants to commit changes. Triggers: '/commit', 'commit changes', 'make a commit'.",
+        argument_hint="[optional context]",
+        arguments=[],
+        user_invocable=True,
+        context="inline",
+        source="builtin",
+    ))
+
+    register_builtin_skill(SkillDef(
+        name="review",
+        description="Review code changes or a pull request and provide structured feedback",
+        triggers=["/review", "/review-pr"],
+        tools=["Bash", "Read", "Grep"],
+        prompt=_REVIEW_PROMPT,
+        file_path="<builtin>",
+        when_to_use="Use when the user wants a code review. Triggers: '/review', '/review-pr', 'review this PR'.",
+        argument_hint="[PR number or URL]",
+        arguments=["pr"],
+        user_invocable=True,
+        context="inline",
+        source="builtin",
+    ))
+
+
+_register_builtins()