deps: pin requires-python = ">=3.14"; commit uv.lock

Match CI + runtime target exactly — both run Python 3.14, so the
package metadata signals consumers that we don't test against 3.12/3.13.

uv.lock is tracked so the test job's `uv venv` resolution is
reproducible (currently the test job installs the editable package
without consulting the lockfile; future work could wire `uv sync` in).
Lockfile resolves 179 packages against Python 3.14.4.

ci-requirements.md updated to drop the prior "permissive lower bound"
caveat.

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

ci-requirements.md

@@ -44,6 +44,6 @@ candidates if more than one project needs them.
   ci-python pulls add ~30s; not a blocker.
 - Registry-backed BuildKit layer cache (`type=registry,ref=…:cache,mode=max`)
   gives ~80% speedup on warm builds — see the build job comment.
-- `pyproject.toml` keeps `requires-python = ">=3.12"` permissive so the
+- `pyproject.toml` pins `requires-python = ">=3.14"` to match the CI +
-  package can still be installed against older interpreters by external
+  runtime target; lockfile (`uv.lock`) is committed and resolves against
-  consumers, but the CI/runtime target is 3.14.
+  Python 3.14.

pyproject.toml

@@ -6,7 +6,7 @@ build-backend = "setuptools.build_meta"
 name = "fabledassistant"
 version = "0.1.0"
 description = "Self-hosted note-taking and task-tracking app with LLM integration"
-requires-python = ">=3.12"
+requires-python = ">=3.14"
 dependencies = [
     "quart>=0.19",
     "sqlalchemy[asyncio]>=2.0",