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Describe the bug

When attempting to extend Flet in development mode using flet run, the custom control development does not work properly. It seems that the custom controls only function in build mode, likely because the pubspec is extended during the bootstrap process for compilation but not in run mode.

Code sample

[Paste your code here]

To reproduce

1. Attempt to create a custom control while running the application in development mode using flet run.
2. Observe that the custom control does not function as expected.
3. Switch to build mode and notice that the custom control works correctly.

Expected behavior

Custom controls should work in both development (flet run) and build modes.

Screenshots / Videos

Operating System

macOS

Operating system details

Sonoma 16.5

Flet version

23.2

Regression

No, it isn't

Suggestions

Adjust the development workflow to ensure that the pubspec is correctly extended during the flet run process, as it is during build mode. This should include compiling the client, enabling custom controls to be compiled and function properly in development mode.

Logs

[Paste your logs here]

Additional details

No response