Add MkDocs documentation and GitHub Pages deployment

Documentation structure:
- Getting Started: Installation, Quick Start
- User Guide: Terminal, Python API, Commands Reference
- Architecture: Overview, Content Addressing
- API Reference: DagShell, FileSystem

GitHub Actions workflow for automatic deployment to GitHub Pages.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: queelius

.github/workflows/docs.yml

@@ -0,0 +1,50 @@
+name: Deploy Documentation
+
+on:
+  push:
+    branches:
+      - main
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+concurrency:
+  group: "pages"
+  cancel-in-progress: false
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.11'
+
+      - name: Install dependencies
+        run: |
+          pip install mkdocs mkdocs-material
+
+      - name: Build documentation
+        run: mkdocs build
+
+      - name: Upload artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: ./site
+
+  deploy:
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    runs-on: ubuntu-latest
+    needs: build
+    steps:
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4

.gitignore

@@ -90,3 +90,4 @@ test_results.txt
 
 # Backup files
 Initial version
+site/

docs/api/dagshell.md

@@ -0,0 +1,256 @@
+# DagShell API
+
+The `DagShell` class provides the main interface for interacting with the virtual filesystem.
+
+## Constructor
+
+```python
+from dagshell.dagshell_fluent import DagShell
+
+shell = DagShell(fs=None)
+```
+
+**Parameters:**
+
+- `fs` - Optional FileSystem instance. Creates new one if not provided.
+
+## Navigation
+
+### cd(path)
+
+Change current directory.
+
+```python
+shell.cd("/home/user")
+shell.cd("..")
+shell.cd("-")  # Previous directory
+```
+
+### pwd()
+
+Return current working directory.
+
+```python
+result = shell.pwd()
+print(result.text)  # /home/user
+```
+
+### pushd(path), popd(), dirs()
+
+Directory stack operations.
+
+```python
+shell.pushd("/tmp")
+shell.popd()
+result = shell.dirs()
+```
+
+## File Operations
+
+### cat(*paths)
+
+Display file contents.
+
+```python
+result = shell.cat("/etc/passwd")
+result = shell.cat("file1.txt", "file2.txt")
+```
+
+### head(n, *paths), tail(n, *paths)
+
+Display first/last n lines.
+
+```python
+result = shell.head(10, "/var/log/messages")
+result = shell.tail(20, "/var/log/messages")
+```
+
+### touch(path)
+
+Create empty file or update timestamp.
+
+```python
+shell.touch("/newfile.txt")
+```
+
+### cp(src, dst), mv(src, dst), rm(path, recursive=False)
+
+Copy, move, remove files.
+
+```python
+shell.cp("/src.txt", "/dst.txt")
+shell.mv("/old.txt", "/new.txt")
+shell.rm("/file.txt")
+shell.rm("/dir", recursive=True)
+```
+
+### mkdir(path, parents=False)
+
+Create directory.
+
+```python
+shell.mkdir("/newdir")
+shell.mkdir("/path/to/dir", parents=True)
+```
+
+### ls(path=None, all=False, long=False)
+
+List directory contents.
+
+```python
+result = shell.ls()
+result = shell.ls("/home", all=True, long=True)
+```
+
+## Text Processing
+
+### echo(*args, n=False)
+
+Display text.
+
+```python
+result = shell.echo("Hello", "World")
+shell.echo("no newline", n=True)
+```
+
+### grep(pattern, *files, ignore_case=False, invert=False)
+
+Search for patterns.
+
+```python
+shell.cat("/file.txt")
+result = shell.grep("pattern")
+
+# Or directly
+result = shell.grep("pattern", "/file.txt", ignore_case=True)
+```
+
+### sort(*files, reverse=False, numeric=False, unique=False)
+
+Sort lines.
+
+```python
+result = shell.sort("/data.txt", numeric=True)
+```
+
+### uniq(*files, count=False)
+
+Remove duplicate lines.
+
+```python
+result = shell.uniq("/data.txt", count=True)
+```
+
+### wc(*files, lines=False, words=False, chars=False)
+
+Count lines, words, characters.
+
+```python
+result = shell.wc("/file.txt")
+result = shell.wc("/file.txt", lines=True)
+```
+
+### cut(*files, delimiter='\t', fields=None)
+
+Extract fields.
+
+```python
+result = shell.cut("/data.csv", delimiter=",", fields="1,3")
+```
+
+### tr(set1, set2='', delete=False)
+
+Translate characters.
+
+```python
+shell.cat("/file.txt")
+result = shell.tr("a-z", "A-Z")
+result = shell.tr("0-9", "", delete=True)
+```
+
+### diff(file1, file2, unified=False)
+
+Compare files.
+
+```python
+result = shell.diff("/file1.txt", "/file2.txt")
+result = shell.diff("/old.py", "/new.py", unified=True)
+```
+
+## Links
+
+### ln(target, link, symbolic=False)
+
+Create links.
+
+```python
+shell.ln("/target.txt", "/hardlink.txt")
+shell.ln("/target.txt", "/symlink.txt", symbolic=True)
+```
+
+### readlink(path)
+
+Read symbolic link target.
+
+```python
+result = shell.readlink("/symlink.txt")
+```
+
+## Permissions
+
+### chmod(mode, path)
+
+Change file mode.
+
+```python
+shell.chmod("755", "/script.sh")
+shell.chmod("u+x", "/script.sh")
+shell.chmod("go-w", "/file.txt")
+```
+
+### chown(owner, path)
+
+Change ownership.
+
+```python
+shell.chown("user", "/file.txt")
+shell.chown("user:group", "/file.txt")
+```
+
+### stat(path)
+
+Get file information.
+
+```python
+result = shell.stat("/file.txt")
+```
+
+## Persistence
+
+### save(filename)
+
+Save filesystem to JSON.
+
+```python
+shell.save("backup.json")
+```
+
+### load(filename)
+
+Load filesystem from JSON.
+
+```python
+shell.load("backup.json")
+```
+
+## Output Redirection
+
+CommandResult supports output redirection:
+
+```python
+# Write to file
+shell.echo("content").out("/file.txt")
+
+# Append to file
+shell.echo("more").append("/file.txt")
+```