[ty] Fix analysis override configuration examples (#28683)
## Summary
The generated `overrides.analysis` examples omit the `[[overrides]]`
declaration, so copying them into a configuration file produces a TOML
parsing error. We now include the array declaration and `include =
["src"]` in both the `pyproject.toml` and `ty.toml` examples, matching
the existing rule override examples.
Closes https://github.com/astral-sh/ty/issues/3994.
