docs: Phase 0 Sealing - add Getting Started guide and usage examples

Add comprehensive user documentation for valence-shell:
- GETTING_STARTED.md: Installation, quick start, features, troubleshooting
- EXAMPLES.md: Real-world usage patterns with 10 detailed examples

Completes Component 4 of Phase 0 Sealing plan.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: Test

impl/rust-cli/docs/EXAMPLES.md

@@ -0,0 +1,381 @@
+# Valence Shell - Usage Examples
+
+Real-world usage patterns for valence-shell operations.
+
+---
+
+## Example 1: Project Scaffolding with Rollback
+
+Create a project structure, verify it works, or rollback if it doesn't:
+
+```bash
+vsh> begin new-project
+[txn:12345678] begin new-project
+
+vsh> mkdir myapp
+[op:23456789] mkdir myapp
+
+vsh> mkdir myapp/src
+[op:34567890] mkdir myapp/src
+
+vsh> mkdir myapp/tests
+[op:45678901] mkdir myapp/tests
+
+vsh> touch myapp/README.md
+[op:56789012] touch myapp/README.md
+
+vsh> touch myapp/src/main.rs
+[op:67890123] touch myapp/src/main.rs
+
+vsh> ls myapp > myapp/structure.txt
+[op:78901234] ls myapp
+
+vsh> commit
+Transaction committed: 6 operations
+```
+
+If you made a mistake:
+
+```bash
+vsh> rollback new-project
+Transaction rolled back: 6 operations
+# All changes undone - clean slate
+```
+
+---
+
+## Example 2: Log File Rotation with Undo
+
+Rotate logs safely with the ability to revert:
+
+```bash
+vsh> ls logs
+📄 app.log
+📄 app.log.1
+📄 app.log.2
+
+vsh> begin log-rotate
+[txn:abcdef01] begin log-rotate
+
+vsh> rm logs/app.log.2
+[op:bcdef012] rm logs/app.log.2
+
+vsh> mv logs/app.log.1 logs/app.log.2
+# (mv not implemented yet - use external command)
+
+vsh> mv logs/app.log logs/app.log.1
+# (external mv not reversible)
+
+vsh> touch logs/app.log
+[op:cdef0123] touch logs/app.log
+
+vsh> commit
+```
+
+Better approach (when you realize external mv isn't reversible):
+
+```bash
+vsh> rollback log-rotate
+# Undoes only the vsh operations (rm, touch)
+
+# Use transaction for atomic rotation
+# (Feature request: Built-in mv command)
+```
+
+---
+
+## Example 3: Batch File Operations
+
+Create multiple files with redirection:
+
+```bash
+vsh> begin batch-create
+[txn:def01234] begin batch-create
+
+vsh> echo "File 1" > file1.txt
+[op:ef012345] echo
+
+vsh> echo "File 2" > file2.txt
+[op:f0123456] echo
+
+vsh> echo "File 3" > file3.txt
+[op:01234567] echo
+
+vsh> ls > inventory.txt
+[op:12345678] ls
+
+vsh> commit
+Transaction committed: 4 operations
+```
+
+Undo creates and writes:
+
+```bash
+vsh> undo 4
+[op:23456789] undo [op:12345678] DeleteFile inventory.txt
+[op:34567890] undo [op:01234567] DeleteFile file3.txt
+[op:45678901] undo [op:f0123456] DeleteFile file2.txt
+[op:56789012] undo [op:ef012345] DeleteFile file1.txt
+```
+
+---
+
+## Example 4: Redirection Pipelines
+
+### Capture Command Output
+
+```bash
+vsh> ls -la > full-listing.txt
+[op:67890123] ls
+# Long listing saved to file
+
+vsh> cat full-listing.txt
+drwxr-xr-x  project/
+-rw-r--r--  README.md
+```
+
+### Append to Logs
+
+```bash
+vsh> echo "[INFO] Starting process" >> app.log
+[op:78901234] echo
+
+vsh> date >> app.log
+[op:89012345] date
+
+vsh> echo "[INFO] Process complete" >> app.log
+[op:90123456] echo
+
+vsh> cat app.log
+[INFO] Starting process
+Tue Jan 28 14:30:00 UTC 2026
+[INFO] Process complete
+```
+
+### Error Logging
+
+```bash
+vsh> find /restricted 2> errors.log
+# Permission errors captured in errors.log
+
+vsh> cat errors.log
+find: /restricted: Permission denied
+```
+
+---
+
+## Example 5: Verification Workflow
+
+Verify operations with proof references:
+
+```bash
+vsh> mkdir build --verbose
+[op:01234567] mkdir build
+    Proof: mkdir_rmdir_reversible (FilesystemModel.lean:158)
+    Undo: rmdir build
+
+vsh> history --proofs
+═══ Operation History ═══
+
+[01234567] 14:30:00 mkdir build
+    Theorem: mkdir_rmdir_reversible (FilesystemModel.lean:158)
+```
+
+---
+
+## Example 6: Safe Cleanup
+
+Clean up temporary files with undo safety:
+
+```bash
+vsh> begin cleanup
+[txn:12345678] begin cleanup
+
+vsh> rm temp1.txt
+[op:23456789] rm temp1.txt
+
+vsh> rm temp2.txt
+[op:34567890] rm temp2.txt
+
+vsh> rmdir temp-dir
+[op:45678901] rmdir temp-dir
+
+vsh> commit
+Transaction committed: 3 operations
+```
+
+If you accidentally deleted something important:
+
+```bash
+vsh> undo 3
+# All files restored from undo data
+```
+
+---
+
+## Example 7: Operation Independence
+
+Operations on different paths don't interfere:
+
+```bash
+vsh> mkdir alpha
+[op:56789012] mkdir alpha
+
+vsh> mkdir beta
+[op:67890123] mkdir beta
+
+vsh> undo
+[op:78901234] undo [op:67890123] rmdir beta
+
+vsh> ls
+📁 alpha/
+# beta removed, alpha unaffected
+```
+
+---
+
+## Example 8: Transaction Rollback
+
+Rollback when operations fail mid-transaction:
+
+```bash
+vsh> begin risky
+[txn:89012345] begin risky
+
+vsh> mkdir test
+[op:90123456] mkdir test
+
+vsh> touch test/file.txt
+[op:01234567] touch test/file.txt
+
+# Oops - need to abort
+vsh> rollback risky
+Transaction rolled back: 2 operations
+
+vsh> ls test
+Error: Path does not exist
+# Everything cleaned up
+```
+
+---
+
+## Example 9: Redirected Undo
+
+File modifications are tracked:
+
+```bash
+vsh> echo "version 1" > data.txt
+[op:12345678] echo
+
+vsh> cat data.txt
+version 1
+
+vsh> echo "version 2" > data.txt
+[op:23456789] echo
+
+vsh> cat data.txt
+version 2
+
+vsh> undo
+[op:34567890] undo [op:23456789] WriteFile data.txt
+# File truncation reversed - original content restored
+
+vsh> cat data.txt
+version 1
+```
+
+---
+
+## Example 10: Interrupting Long Commands
+
+Ctrl+C stops external commands:
+
+```bash
+vsh> sleep 300
+# Press Ctrl+C after a few seconds
+^C
+[Interrupted - exit code 130]
+
+vsh> # Shell still responsive
+```
+
+---
+
+## Common Patterns
+
+### Pattern: Experimental Changes
+
+```bash
+begin experiment
+# Make changes
+# Test them
+commit  # If good
+# OR
+rollback experiment  # If bad
+```
+
+### Pattern: Staged Operations
+
+```bash
+mkdir stage1
+touch stage1/file.txt
+# Verify stage1 works
+mkdir stage2
+# Verify stage2 works
+# All operations are individually undoable
+```
+
+### Pattern: Redirection with Undo Safety
+
+```bash
+ls > backup-listing.txt
+# Oops - wrong file
+undo
+# File deleted automatically
+ls > correct-listing.txt
+```
+
+---
+
+## Advanced Usage
+
+### Operation Graph Navigation
+
+```bash
+vsh> graph
+# Shows current state in DAG
+
+vsh> history
+# Shows linear history
+
+vsh> undo
+# Move backward in DAG
+
+vsh> redo
+# Move forward in DAG
+```
+
+### Proof Verification
+
+Every operation corresponds to a Lean 4 theorem:
+
+| Operation | Theorem | File |
+|-----------|---------|------|
+| mkdir | mkdir_rmdir_reversible | FilesystemModel.lean:158 |
+| rmdir | rmdir_mkdir_reversible | FilesystemModel.lean:184 |
+| touch | createFile_deleteFile_reversible | FileOperations.lean:42 |
+| rm | deleteFile_createFile_reversible | FileOperations.lean:52 |
+| > | truncate_restore_reversible | FileContentOperations.lean:109 |
+| >> | append_truncate_reversible | FileContentOperations.lean:297 |
+
+---
+
+## Next Steps
+
+- Read [PHASE6_M2_COMPLETE.md](PHASE6_M2_COMPLETE.md) for technical details
+- Explore `proofs/lean4/` for formal verification
+- Try building your own verified operations
+
+---
+
+**Remember**: vsh is a research prototype. Use it to explore formally verified computing, not for production systems (yet).