feat(template): introduce selector configuration for all template types

[lalvarezt]

📺 PR Description

This PR closes #708, see discussion for additional information

One-to-One

[metadata]
name = "git-diff2"
description = "A channel to select files from git diff commands"
requirements = ["git"]

[source]
command = "git log --graph --pretty=format:'%C(yellow)%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset' --abbrev-commit --color=always"
output = "{strip_ansi|split: :1}"
ansi = true

[ui]
results_max_selections = 2

[ui.preview_panel.footer]
template = "diff {strip_ansi|split: :1}..{strip_ansi|split: :1}"
mode = "one_to_one"

[preview.command]
template = "git diff --color=always {strip_ansi|split: :1}..{strip_ansi|split: :1}"
mode = "one_to_one"
shell_escaping = true

Concatenate

[metadata]
name = "files"
description = "A channel to select files and directories"
requirements = ["fd", "bat"]

[source]
command = ["fd -t f", "fd -t f -H"]

[source.output]
template = "{}"
mode = "concatenate"
separator = "\n"
shell_escaping = false

[ui.preview_panel.footer]
template = "{}"
mode = "concatenate"
separator = " - "
shell_escaping = false

[preview.command]
template = "bat -n --color=always {}"
# mode = "concatenate"
# separator = " "
shell_escaping = true
env = { BAT_THEME = "ansi" }

[keybindings]
shortcut = "f1"
alt-e = "actions:edit"

[actions.edit]
description = "Opens the selected entries with the default editor (falls back to vim)"
# use `mode = "fork"` if you want to return to tv afterwards
mode = "execute"

[actions.edit.command]
template = "${EDITOR:-vim} {}"
mode = "concatenate"
separator = " "
shell_escaping = true

Checklist

• my commits and PR title follow the conventional commits format
• if this is a new feature, I have added tests to consolidate the feature and prevent regressions
• if this is a bug fix, I have added a test that reproduces the bug (if applicable)
• I have added a reasonable amount of documentation to the code where appropriate