refactor: restructure mytoolkit with new subcommands and md-to-pdf improvements

- Add new subcommands: convert, preflight, server, templates, webpage
- Migrate config from bin/config.json to ~/.config/mytoolkit
- Fix expand_bookmarks to modify writer objects instead of reader
- Improve md_to_pdf with CJK bookmark support
- Update README and project metadata

bin/commands/webpage.py

@@ -0,0 +1,89 @@
+"""Webpage project utilities (Docusaurus build / clear / etc.).
+
+Project metadata lives in `server.py` so that adding a new webpage there
+automatically wires it up here.
+"""
+
+import subprocess
+import time
+
+import click
+
+from bin.commands.server import manageable_services, get_service, no_color_env
+
+
+_PROJECTS = manageable_services()
+_NAMES = [s.name for s in _PROJECTS]
+
+
+def _run_npm(name: str, script: str, label: str) -> None:
+    """Run `npm run <script>` in the project's directory, streaming output."""
+    svc = get_service(name)
+    assert svc.project_dir is not None  # _NAMES is manageable services only
+
+    if not svc.project_dir.exists():
+        click.secho(f"Project directory not found: {svc.project_dir}", fg="red")
+        raise click.Abort()
+
+    click.secho(f"{label} {svc.name} ({svc.description}) ...", fg="cyan")
+    started = time.time()
+    proc = subprocess.run(["npm", "run", script], cwd=svc.project_dir, env=no_color_env())
+    elapsed = time.time() - started
+    if proc.returncode != 0:
+        click.secho(f"{script} failed for {svc.name} (exit {proc.returncode})", fg="red")
+        raise click.Abort()
+    click.secho(f"{svc.name} {script} done in {elapsed:.1f}s", fg="green")
+
+
+@click.group(name="webpage")
+def webpage_cmd():
+    """Manage Docusaurus webpage projects."""
+    pass
+
+
+@webpage_cmd.command("list")
+def webpage_list():
+    """List managed webpage projects and their build status."""
+    click.echo("")
+    click.secho(
+        f"{'Name':<16} {'Build':<12} {'Description':<36} {'Project'}",
+        fg="bright_blue",
+        bold=True,
+    )
+    click.echo("-" * 100)
+    for svc in _PROJECTS:
+        assert svc.project_dir is not None  # _PROJECTS is manageable services only
+        build_dir = svc.project_dir / "build"
+        if build_dir.exists():
+            build_status = time.strftime("%m-%d %H:%M", time.localtime(build_dir.stat().st_mtime))
+            color = "green"
+        else:
+            build_status = "missing"
+            color = "yellow"
+        click.secho(
+            f"{svc.name:<16} {build_status:<12} {svc.description:<36} {svc.project_dir}",
+            fg=color,
+        )
+    click.echo("")
+
+
+@webpage_cmd.command("build")
+@click.argument("name", type=click.Choice(_NAMES, case_sensitive=False))
+def webpage_build(name):
+    """Build a webpage project (`npm run build`)."""
+    _run_npm(name, "build", "Building")
+
+
+@webpage_cmd.command("clear")
+@click.argument("name", type=click.Choice(_NAMES, case_sensitive=False))
+def webpage_clear(name):
+    """Clear Docusaurus build artifacts and cache (`npm run clear`)."""
+    _run_npm(name, "clear", "Clearing")
+
+
+@webpage_cmd.command("rebuild")
+@click.argument("name", type=click.Choice(_NAMES, case_sensitive=False))
+def webpage_rebuild(name):
+    """Clear cache then build (`npm run clear && npm run build`)."""
+    _run_npm(name, "clear", "Clearing")
+    _run_npm(name, "build", "Building")