chore: update all package dependencies and run security audit

**Depends on #354 (monorepo migration).** Done as the first PR after the monorepo lands, setting correct versions in each new per-package `pyproject.toml`.

JS reference: [PR #1028](https://github.com/hashgraph/hedera-agent-kit-js/pull/1028) (`chore: update dependencies across examples and packages`)
Related: #200, #279

## Scope

- Bump `hiero-sdk-python`, `langchain`, `langchain-openai`, `langchain-anthropic`, `langchain-groq`, `google-adk`, `mcp`, `langchain-mcp-adapters`, `web3` to latest stable in each relevant package
- Bump all dev deps (`black`, `ruff`, `pytest-asyncio`, `pytest-timeout`, etc.)
- Run `pip-audit` across all packages; resolve any reported CVEs
- Commit updated `uv.lock`

Wait for the monorepo migration in #354, then inspect each package's pyproject.toml and the updated uv.lock. Bump the listed runtime and development dependencies, run pip-audit across all packages, resolve reported CVEs, and confirm the lockfile is committed.

Written by the indexing model from the issue text.