Show First Transaction Panics

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System Information

Version:  v0.2.1-modified

System: windows/arm64

Go:  go1.24.4

Source Revision:  11fe14208d539d4ff4237e3c06428836b8a9d823

## What did you do?

I executed `baronial show` on the first transaction in a repository.

## What did you expect to happen?

I expected a text representation of each field of a transaction displayed.

## What actually happened?

Go had a panic, and a stack trace gets dumped.

Stack Trace

panic: runtime error: index out of range [0] with length 0


goroutine 1 [running]:

github.com/marstr/baronial/internal/format.PrettyPrintTransaction({0x7ff709a7eda0?, 0x4000068000?}, {0x7ff709a7c8f8?, _}, {_, _}, {0x4000094d10, {0x0, 0x0, 0x0}, ...})

        C:/Users/marstr/code/github.com/marstr/baronial/internal/format/transaction.go:101 +0x5a8

github.com/marstr/baronial/cmd.init.func16(0x40000d8d00?, {0x4000094aa0, 0x1, 0x7ff7099fe688?})

        C:/Users/marstr/code/github.com/marstr/baronial/cmd/show.go:68 +0x2d0

github.com/spf13/cobra.(*Command).execute(0x7ff709c782a0, {0x4000094a60, 0x1, 0x1})

        C:/Users/marstr/go/pkg/mod/github.com/spf13/cobra@v1.9.1/command.go:1019 +0x82c

github.com/spf13/cobra.(*Command).ExecuteC(0x7ff709c75c20)

        C:/Users/marstr/go/pkg/mod/github.com/spf13/cobra@v1.9.1/command.go:1148 +0x384

github.com/spf13/cobra.(*Command).Execute(...)

        C:/Users/marstr/go/pkg/mod/github.com/spf13/cobra@v1.9.1/command.go:1071

github.com/marstr/baronial/cmd.Execute()

        C:/Users/marstr/code/github.com/marstr/baronial/cmd/root.go:85 +0x24

main.main()

        C:/Users/marstr/code/github.com/marstr/baronial/main.go:21 +0x1c

Start in internal/format/transaction.go at line 101, where PrettyPrintTransaction panics, and trace its call from cmd/show.go. Reproduce with baronial show on the first transaction, then verify that every transaction field is printed without a panic.

Written by the indexing model from the issue text.