closes#6909
related to forgejo/design#14
# Description
Adds the following boolean operators for issues when using an indexer (with minor caveats)
- `+term`: `term` MUST be present for any result
- `-term`: negation; exclude results that contain `term`
- `"this is a term"`: matches the exact phrase `this is a term`
In all cases the special characters may be escaped by the prefix `\`
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/6952
Reviewed-by: 0ko <0ko@noreply.codeberg.org>
Reviewed-by: Otto <otto@codeberg.org>
Co-authored-by: Shiny Nematoda <snematoda.751k2@aleeas.com>
Co-committed-by: Shiny Nematoda <snematoda.751k2@aleeas.com>
