git_ui: Disable remote button during operations (#59874)

# Objective

This change prevents users from starting multiple Git remote operations
at the same time from the Git panel. Fetch, pull, and push can take
time, may prompt for credentials, and can update shared repository
state, so allowing repeated clicks can create duplicated work, confusing
UI feedback, or overlapping Git commands.


## Solution

The panel now records when a remote operation is in progress, disables
the main remote action button, and shows a clear tooltip such as “Push
in progress.” When the async task exits, the state is cleared and the
button is re-enabled. This keeps the UI aligned with the operation
lifecycle and makes repeated clicks harmless.

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Release Notes:

- Git: Improved performance by not allowing multiple remote Git
operation to start at the same time.

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Signed-off-by: Xiaobo Liu <cppcoffee@gmail.com>
Co-authored-by: Danilo Leal <daniloleal09@gmail.com>
e7afe9fcf9Xiaobo Liu committed on 6/25/2026, 1:17:06 PM· committed by GitHubparent6e085b2
2 files changedLine totals unavailable