fix: char-safe table cell truncation

[platinummonkey]

What does this PR do?

Fixes a panic in the -o table formatter when a cell value longer than the column cap is cut inside a multi-byte UTF-8 character. Cell truncation now cuts on character boundaries via a shared truncate_ellipsis helper instead of slicing by byte index.

Motivation

src/formatter.rs truncated table cells with byte-index slices (&s[..47], &s[..13], &result[..47]). Any value whose cut point landed inside a multi-byte character panicked, e.g. end byte index 47 is not a char boundary; it is inside 'è'. This makes pup monitors list -o table (and any table with non-ASCII cells: dashboard titles, log messages, incident titles, tags) crash for non-English orgs. comfy_table already handles display-width column alignment, so a character-boundary cap is sufficient to both stop the panic and keep alignment correct — no new dependency required. Closes #676.

Changes

• Add truncate_ellipsis(s, max) helper in src/commands/../formatter.rs (src/formatter.rs) that counts characters and cuts on char boundaries, appending ... when shortened.
• Replace the three byte-index truncation sites in format_cell (string and array paths) and format_array_item with calls to the helper.
• Add regression tests: a long accented monitor-name string (the exact value from the report) and an accented array-preview value, asserting no panic and correct character-count truncation.

Additional Notes

Existing ASCII behavior is unchanged (byte length equals char count), so prior tests and outputs are preserved. Full cargo test/clippy could not be executed in the sandbox because the datadog-api-client git dependency is unreachable; the truncation logic and test assertions were verified with a standalone rustc build and rustfmt --check passes on the file.

Checklist

• The code change follows the project conventions (see CONTRIBUTING.md)
• Tests have been added/updated (if applicable)
• Documentation has been updated (if applicable)
• All CI checks pass
• Code coverage is maintained or improved

Related Issues

Closes #676

---

PR by Bits - View session in Datadog

Comment @DataDog to request changes

[datadog-prod-us1-3]

View session in Datadog

Bits Code status: ✅ Done

Comment @DataDog to request changes

[datadog-datadog-prod-us1]

I can only run on private repositories.