chore: bootstrap repo (pyproject, uv lockfile, Python 3.14, MIT license)

[constk]

Problem

The repository is empty. Every other harness layer needs Python project metadata, a reproducible lockfile, an enforced Python version, and a license before it can land.

Proposed solution

Add pyproject.toml with name = "harness-python-react", version = "0.1.0", requires-python = ">=3.14", and minimal seed deps (FastAPI, Pydantic v2; no domain deps). Run uv lock against Python 3.14. Add LICENSE (MIT) and a stub README.md (full README ships in #26).

Acceptance criteria

• pyproject.toml present; project name harness-python-react; requires-python = ">=3.14".
• uv.lock committed; uv sync succeeds on Python 3.14.
• LICENSE (MIT) at repo root, copyright holder filled in.
• Stub README.md describes the project in 2-3 sentences.
• Bootstrap PR opened against develop and merged.

Priority rationale

Critical and blocking: every other ticket assumes pyproject, lockfile, and license exist.

Depends on

None

[constk]

Bootstrap merged via #29 (squashed to develop). pyproject + uv.lock + LICENSE + README stub all in place; uv sync verified on Python 3.14.3.