feat: multi-column results with fuzzy filtering (e.g. %p in helix)

[delafthi]

Problem

When channel entries carry multiple logical fields (e.g. <name> <group>, <path> <symbol>, or <name> <id>), the fuzzy search operates on the entire concatenated string. There's no way to target a specific field independently.

Feature

Allow channel definitions to declare "columns" in the results pane. Each column maps to a named field of the entry and can optionally participate in fuzzy matching via a prompt modifier (similar to how %p already works for path filtering in Helix, see https://docs.helix-editor.com/pickers.html#filtering-picker-results).

• Display-only columns — extra fields rendered in the results pane but not included in the default fuzzy match (useful for annotations like timestamps, tags, counts).
• Searchable columns — fields that can be targeted explicitly in the prompt using a %<key> modifier.

Example prompt syntax:

<term for col1> %<specifier> <term for col2>

This would fuzzy-match <term for col1> against the primary column and <term for col2> against the namespace column independently.

Examples

A custom channel emitting <project> <namespace> pairs could declare:

[[channel.entries]]
columns = [
  { field = "name", searchable = true },
  { field = "group", searchable = true, modifier = "g" },
]

Prompt usage:

foo %g bar

→ fuzzy-filters entries where the name matches foo and the groups matches bar.

For a file+symbol channel:

columns = [
  { field = "path", searchable = true, modifier = "p" },
  { field = "symbol", searchable = true },
  { field = "kind", searchable = false },   # display-only (e.g. "fn", "struct")
]

Prompt:

parse %p src/parser

→ symbols matching parse inside files matching src/parser, with kind shown as an annotation column.

Additional context

This would make television significantly more powerful for structured data sources where entries are naturally multi-dimensional. The %p convention already feels familiar to Helix users, so extending it to arbitrary named columns should be intuitive. Display-only columns also open the door to richer and visually more appealing UIs.

Just putting this out here. I haven't thought about the implementation and would be happy to know what others think.