Add text overflow modes and adaptive columns

[noponoponopo]

Context of Contribution

• Bug Fix
• Refactoring
• New Feature
• Others

Summary of the Proposal

This pull request adds an optional textOverflow field to Custom Metrics snapshots.

Three behaviors are available:

• truncate keeps text on one line without widening its column.
• wrap uses multiple lines without widening its column.
• expand allows content to widen its column.

The default is expand, which preserves the existing behavior.

The dashboard adds another column only when its content would exceed the visible screen height. Column heights are measured again after their widths are established so wrapped text is placed correctly.

A single card that exceeds the available height becomes internally scrollable.

All 136 tests pass.

Reason for the new feature

Custom Metrics values can contain long titles, paths, descriptions, or generated text. A single overflow behavior cannot serve both compact status cards and cards that need to display complete text.

The new modes let each producer choose between compact truncation, complete wrapped text, and the existing expanding behavior.

Adaptive columns keep larger sets of cards visible without requiring a permanently wider dashboard. The existing behavior remains the default, so current JSON files do not require migration.

Checklist

• I have read the CONTRIBUTING.md and agree to follow it.
• This PR does not contain commits of multiple contexts.
• Code follows proper indentation and naming conventions.
• Implemented using only APIs that can be submitted to the App Store.

[noponoponopo]

PR#37と#39が前提となっています

[noponoponopo]

一連の4つのPR#37~#40を実装した場合の実際の見た目
はこのようになります。

[Kyome22]

I get the impression that this significantly departs from RunCat's philosophy of "simplicity."