bim-table cell content truncated for long values — shadow DOM styles prevent fix

[luisdm-dev]

Describe the bug 📝

Values that are longer than the column's rendered width are silently clipped/truncated inside bim-table. The value is present in the data but not visible in the UI. This affects long ASCII strings (e.g. GUIDs)

The internal / label elements inside bim-table's shadow DOM have white-space: nowrap and overflow: hidden (or equivalent) with no text-overflow: ellipsis and no way to expand. Because these styles live inside the shadow root, we cannot override them with external CSS — even with !important injected into shadowRoot — because child rows and labels have their own nested shadow roots that are not reachable without explicit part or exportparts exposure.

Expected behavior:

Long values should either wrap, truncate with a visible ellipsis + tooltip, or the column should be horizontally scrollable.
At minimum, exportparts should be exposed on bim-table so host apps can style cell content themselves.

Reproduction ▶️

https://docs.thatopen.com/Tutorials/UserInterface/OBC/ItemsData

Steps to reproduce 🔢

1. Load an IFC model where element names or property values contain long strings.
2. Select an element and inspect the Properties Panel
3. Observe that some Value cells show nothing or are cut off, even when the same row's Name cell with a shorter string renders fine.

Example (GUID, Name, and NominalValue not showing):

Example (Name, ObjectType, Tag, etc. not showing):

System Info 💻

System:
    OS: macOS 15.5
    CPU: (8) arm64 Apple M2
    Memory: 96.92 MB / 16.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 22.12.0 - /Users/luisdemesa/.local/state/fnm_multishells/46201_1776408853044/bin/node
    npm: 10.9.0 - /Users/luisdemesa/.local/state/fnm_multishells/46201_1776408853044/bin/npm
  Browsers:
    Chrome: 147.0.7727.56
    Safari: 18.5

Used Package Manager 📦

npm

Error Trace/Logs 📃

No response

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