chore(deps): bump charset-normalizer 3.4.7, claude-agent-sdk 0.1.54

Recompiled requirements.txt from pyproject.toml via uv pip compile.
Both packages pass the 7-day exclude-newer supply-chain gate.

- charset-normalizer 3.4.6 → 3.4.7 (released 2026-04-02)
- claude-agent-sdk 0.1.50 → 0.1.54 (released 2026-04-02)

Dependabot PRs #110 (pydantic-core), #111 (cryptography), #113
(claude-agent-sdk 0.1.58) propose versions blocked by the 7-day rule.
PR #109 (importlib-metadata 9.0.0) also blocked by UV exclude-newer.

Author: datasciencemonkey