feat: add journal submission kits + paper scaffold; restructure package

- init journal <elsevier|ieee|springer>: self-contained, make-buildable kits
  (Springer sn-jnl.cls + bst bundled; reuses project references.bib)
- init paper scaffold: ctexart + Fandol fonts, bib at root, latexdiff highlighted
- move templates/ under mytoolkit/, add info/references, relocate protocols
- migrate mytoolkit skill into submodule; update README/CLAUDE docs

README.md

@@ -5,20 +5,33 @@ Personal CLI toolkit — unified entry point for everyday file conversion, forma
 ## Install
 
 ```bash
-make install                                  # builds + symlinks ~/.local/bin/mytoolkit
+make install                                  # install CLI + sync bundled Claude skill
 mytoolkit --version
-mytoolkit templates register ~/workspace/contrib/mytoolkit/templates   # one-time, points at template root
+mytoolkit templates list                      # verify bundled templates are found
+```
+
+`make install` 会同时：
+1. 用 editable 模式安装 `mytoolkit`；
+2. 生成 zsh/bash 补全；
+3. 把 bundled Claude skill 同步到 `~/.claude/skills/mytoolkit/`。
+
+单独同步 skill（不重装 Python 包）：
+
+```bash
+make sync-skill
 ```
 
 ## Update
 
-The installed Python package is **not** refreshed automatically when the source tree changes. After editing source files, or after `git pull` / `git submodule update`, rerun:
+The installed Python package and the bundled Claude skill are **not** refreshed automatically when the source tree changes. After editing source files, skill docs, or after `git pull` / `git submodule update`, rerun:
 
 ```bash
 make install            # or: mytoolkit update
 mytoolkit --version     # verify the new version is active
 ```
 
+If you only changed skill files (`SKILL.md` / `references/`), `make sync-skill` is enough.
+
 ## Top-level commands
 
 ```bash
@@ -28,6 +41,8 @@ mytoolkit --help
 | Command | What it does |
 |---------|--------------|
 | `convert` | Universal format conversion (md/img/pdf/eps/avi/bib → pdf/docx/tiff/mp4/md). Auto-detects from extensions. |
+| `init` | Initialize projects/kits from bundled templates (`mytoolkit init paper <dir>`, `mytoolkit init journal <name>`) |
+| `info` | Show bundled resource paths (`info paths`, `info docs <name>`) |
 | `pdf` | `compress` / `crop` / `merge` / `bookmark` / `to-tiff` |
 | `image` | `compress` / `eps-fix` / `eps-to-pdf` / `jpg-to-pdf` / `tiff-to-pdf` / `tiff-compress` / `generate` (Doubao/Seedream) |
 | `latex` | `compile` / `count` |
@@ -35,7 +50,7 @@ mytoolkit --help
 | `video` | `avi-to-mp4` |
 | `webpage` | Docusaurus build/list/rebuild/push |
 | `mail` | IMAP/SMTP client (read/draft/forward/reply, no auto-send) |
-| `templates` | Register and inspect external template root |
+| `templates` | Inspect template root; external override still possible |
 | `env` | Manage stored vars (api keys, paths, feishu app credentials) |
 | `ssh` | `list` / `connect` / `tunnel` / `cmd` |
 | `git` | `proxy` (set/unset/list/status) |
@@ -47,19 +62,42 @@ For any subcommand: `mytoolkit <cmd> --help`.
 
 ## Templates
 
-`mytoolkit convert -t <name>` reads templates from an external directory you register (templates are not bundled). Layout:
+`mytoolkit convert -t <name>` reads templates bundled with the package by default. External overrides are still supported via `mytoolkit templates register`.
+
+Bundled layout:
 
 ```
-<root>/md-to-pdf/<name>/template.typ
-<root>/md-to-docx/<name>/template.docx
+mytoolkit/templates/md-to-pdf/<name>/template.typ
+mytoolkit/templates/md-to-docx/<name>/template.docx
 ```
 
 ```bash
-mytoolkit templates register /path/to/templates
-mytoolkit templates list       # lists each template with its absolute path
+mytoolkit templates list       # lists bundled templates with absolute paths
+mytoolkit templates register /path/to/templates   # optional external override
 ```
 
-Registry is stored at `~/.mytoolkit/templates.json` (or `$MYTOOLKIT_HOME/templates.json`).
+Registry is stored at `~/.mytoolkit/templates.json` (or `$MYTOOLKIT_HOME/templates.json`). When the registry is missing or invalid, mytoolkit falls back to the bundled templates.
+
+## Project scaffolds
+
+```bash
+mytoolkit init paper <dir>     # create a LaTeX paper project (ctexart + Fandol fonts)
+```
+
+This generates `main.tex`, `Makefile`, `references.bib`, `diffpreamble.dtx`, `figs/`, `analysis/`.
+
+### Journal submission kits
+
+```bash
+mytoolkit init journal                # list available kits
+mytoolkit init journal elsevier       # -> ./submit-elsevier/
+mytoolkit init journal ieee mydir     # custom target dir
+```
+
+Kits (`elsevier` / `ieee` / `springer`) are self-contained — `main.tex`, a
+pdflatex+bibtex `Makefile`, and any non-bundled class files (Springer's
+`sn-jnl.cls` + `bst/`). Each compiles standalone with `make`, and reuses the
+current directory's `references.bib` if present.
 
 ## User config