Add Record and Stop controls to the sensor graph

[BelhsanHmida]

Let users create pending sensor values by entering a recording mode and clicking directly in the sensor graph.

Acceptance criteria

• Show a Record control with a clear recording symbol on the sensor page.
• Replace Record with Stop while recording is active.
• Convert graph clicks to event starts aligned to the sensor resolution.
• Allow the user to enter or adjust the value associated with each click.
• Display pending values distinctly from existing sensor data.
• Allow pending values to be edited or removed before submission.
• Stop ends the recording session without silently writing values.
• Cancelling discards pending values after confirmation.
• Hide or disable recording controls when the user lacks permission to create data.
• Work with the sensor's configured timezone without changing it.

Tests

• Record/Stop state transitions.
• Click alignment to sensor resolution.
• Editing and removing pending values.
• Permission-based visibility.
• Cancelling a recording session.

Out of scope

• Recurrence expansion details.
• Immediate database writes on each graph click.