This pull request updates how long configuration option names are
displayed in the UI to better handle Unicode characters, ensuring that
names are truncated by grapheme clusters (user-perceived characters)
rather than bytes or code points. This prevents visual glitches with
multi-codepoint characters like emojis or accented letters. The main
changes are:

**Unicode handling improvements:**

* Added the `unicode-segmentation` crate as a workspace dependency in
`Cargo.toml` to support grapheme-aware string operations.
* Updated import statements in `config_options.rs` to include
`unicode_segmentation::UnicodeSegmentation`.

**UI display logic:**

* Changed the truncation logic for configuration option display names in
`ConfigOptionSelector` to use `.graphemes(true).take(32)` instead of
slicing bytes, ensuring proper handling of Unicode graphemes.

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Release Notes:

- Agent: Made label truncation of configuration options in the agent
panel more robust against non-single-byte characters like emojis and
others.

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Co-authored-by: Danilo Leal <daniloleal09@gmail.com>