Bump v0.6.0 (#55)

* chore: draft 0.6.0 changelog and update README with merge() method

* Bump 0.5.0 -> 0.6.0

* Fix duplication in 0.6.0 changelog

Author: nathanjmcdougall

CHANGELOG.md

@@ -60,6 +60,37 @@
 - Added `test_api_contracts` to verify Editor/Document method coverage and consistency.
 - Added tests verifying `NodeTypeError` is catchable as both `PatchError` and `TypeError`.
 
+## 0.6.0
+
+### Features
+
+- Added `merge()` method to `Document` and `Editor` for recursive mapping merging with deep value updates.
+- Added `find_index()` for searching list-of-dicts by matching fields, returning the index of the first matching element.
+- Added `ensure_in_list()` for appending a value to a list only if it's not already present.
+- Added `RoutingError(PatchError)` to the error hierarchy for non-mapping route failures. Operations that attempt to navigate through non-mapping nodes now raise `RoutingError` instead of generic errors.
+- Enhanced error messages with human-readable path formatting in `NodeTypeError` messages for clarity.
+- Added basedpyright type checking for improved static type verification.
+
+### Fixes
+
+- Fixed naive colon finder that corrupted quoted keys containing colons.
+- Replaced unsafe byte indexing with upfront span validation to prevent index-out-of-bounds errors.
+- Fixed nested dict flattening in `_create_at` that could lose intermediate keys during upsert operations.
+- Added support for upsert operations into empty documents without requiring sentinel workaround.
+
+### Internal
+
+- Centralized patch-error classification and applied stepdown rule for better error type hierarchy management.
+
+### Documentation
+
+- Added `NodeTypeError` and `RoutingError` to README error hierarchy documentation.
+
+### Testing
+
+- Added `test_api_contracts` to verify Editor/Document method coverage and consistency.
+- Added tests verifying `NodeTypeError` is catchable as both `PatchError` and `TypeError`.
+
 ## 0.5.0
 
 ### Features