fix: bump __version__ to 0.18.0 (was stale at 0.14.0)

app/__init__.py has been hardcoded to "0.14.0" since the v0.14 release.
Every release between v0.15 and v0.18 updated CHANGELOG and tagged Git
but left __version__ untouched, so the deployed openapi.json kept
reporting 0.14.0. Bumping to match the current release.

Future releases need to update __version__ alongside CHANGELOG until
version derivation is automated (CHANGELOG.md isn't copied into the
container image, so the obvious read-from-CHANGELOG approach won't
work without Dockerfile changes).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: bk86a

CHANGELOG.md

@@ -6,6 +6,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/).
 
 ## [Unreleased]
 
+### Fixed
+
+- **`__version__` was stale at `0.14.0`** since the v0.14 release; openapi.json and FastAPI's `version` field have been reporting the wrong number for every release since then. Bumped to `0.18.0`. Future releases need to update `app/__init__.py` alongside the CHANGELOG until version derivation is automated.
+
 ## [0.18.0] - 2026-05-01
 
 ### Added

app/__init__.py

@@ -1 +1 @@
-__version__ = "0.14.0"
+__version__ = "0.18.0"