Bump python packages to resolve cves (#2394)

## Summary

Remediates two HIGH-severity vulnerabilities in the Python app image:

| Dependency | Previous | Updated | Advisory |
| --- | --- | --- | --- |
| `aiohttp` | 3.13.5 | 3.14.3 | CVE-2026-69244 |
| `cryptography` | 49.0.0 | 50.0.0 | CVE-2026-69247 |

Also updates `pyOpenSSL` from 26.3.0 to 26.4.0 for compatibility with
cryptography 50.

## Validation

- `uv lock --check`
- `pytest packages/kagent-adk/tests -q`
  - 381 passed, 1 skipped
- Verified installed versions:
  - `aiohttp==3.14.3`
  - `cryptography==50.0.0`
  - `pyOpenSSL==26.4.0`

Signed-off-by: Jeremy Alvis <jeremy.alvis@solo.io>

Author: iplay88keys

python/pyproject.toml

@@ -11,8 +11,8 @@ dev = [
 
 [tool.uv]
 constraint-dependencies = [
-    "aiohttp>=3.13.5",
-    "cryptography>=48.0.0",
+    "aiohttp>=3.14.3",
+    "cryptography>=50.0.0",
     "httplib2>=0.32.0",
     "jaraco-context>=6.1.0",
     "joserfc>=1.6.8",