chore: tidy comments that repeat the code or no longer match it

- Comments that only restate a name (sgr, fg, mdLink, the repo provider's starred and current-repo notes) are gone.
- Stale ones match the code again: the repo package covers plain env files too, Launch runs argv, closeVersions no longer claims to move the cursor, and Check's fallback says why rather than naming a state no release had.
- The doc for versionString was attached to pseudo; the backtick in SourcesView's doc was a string-concatenation leftover; openFailed's doc was garbled.
- recentReleases sits next to latest, its user.
- .gitignore drops the Go template's boilerplate and patterns for files this project doesn't make.

internal/ui/styles/theme.go

@@ -131,7 +131,6 @@ type value struct {
 	bold, italic, underline, reverse, faint bool
 }
 
-// fg styles s with the value as foreground, bg as background.
 func (v value) fg(s lipgloss.Style) lipgloss.Style {
 	if v.color != nil {
 		s = s.Foreground(v.color)