Copy-pasting a FK cell should use the value not the record summary

[pavish]

Current behavior

When copying a foreign key cell and pasting the value into a text cell, Mathesar pastes the record summary for the linked record.

Desired behavior

I do not think copying foreign key values should result in pasting the record summary string. I think it should always only be the value stored in the column.

Rationale

• It's essential that the user understands that the record summary is not the content stored on the db, but a summary of the actual referenced row. We already display the values differently on the UI, with a pill.
• What happens when the foreign key is a text column referencing a text column from another table? How would copying such a value into a text column work? (Right now, record summaries will fail for it, but this is a question I'd like us to think about).
• We could make this behaviour configurable in the future, but for now, I think it should directly copy the underlying value.

Additional context

• Originally mentioned in a PR review.

[seancolsen]

@pavish I have a couple questions:

1. We currently have this modal confirmation:

   

   What would you think about utilizing that confirmation dialog to ask the user how they'd like to paste? We could use a radio group like this:

   Paste 2 cells?

   Formatting

   • (•) Paste Formatted Values
   • ( ) Paste Raw Values

   Note that what I'm proposing would also affect other values like dates.

   If this works for you, I would have a slight preference for keeping "Past Formatted Values" as the default choice since I think it's what users would want in most cases. But I'd be open to making "Paste Raw Values" the default if you feel strongly about it.

2. Currently, when copying FK cells and pasting into an application outside Mathesar, the data is serialized to TSV using record summaries. Is this behavior okay with you? This has been the case for a couple years now.

[pavish]

@seancolsen

1. I'm on board with providing an option to let the user choose if they want to paste formatted values or raw values (for any column types containing formatted values - eg., date).

   • However, we should use different text for Foreign keys, since it's not technically "formatting".
   • I'm also on board with keeping the "Paste Formatted Values" as the default choice.

2. Currently, when copying FK cells and pasting into an application outside Mathesar, the data is serialized to TSV using record summaries. Is this behavior okay with you? This has been the case for a couple years now.

   I don't think that this should be the behaviour for FK cells. I think it should paste the raw value and not the record summary. That said, I'm not leaning towards it too strongly. I would just like to have a discussion open. We should consider scenarios such as:

   • What if users are pasting to a competing/similar db product to Mathesar.
   • What if the FK column is a string column or UUID? Users might want to see a name instead of the UUID in the summary but copy the underlying UUID.

[seancolsen]

@pavish I think we're relatively close to figuring out what needs to be done here, but we still have some unanswered questions and open-ended problems to solve. And, while I don't see the implementation being huge, I don't see it being trivial either. So at this point I'm starting to wonder how much of a priority it is to continue hashing this out. Personally, I don't think this needs to go in 0.2.2. Could we put this in Backlog, unassign me from it, and pick it up later when it becomes a higher priority?