Bash completion script omits --focus-column / --focus-length flags

[Widthdom]

Summary

The bash completion script for excerpt is missing --focus-column and --focus-length flags even though the zsh / fish completions include them. Bash users typing cdidx excerpt … --focus- get no autocomplete.

Evidence

• src/CodeIndex/Cli/ConsoleUi.cs:589-631 — bash-completion table for excerpt omits the two flags.

Impact

• Discoverability gap for bash users.
• Inconsistent UX between shells.

Proposed direction

• Add --focus-column and --focus-length to the bash completion list.
• Add a small test that compares the bash, zsh, and fish completion outputs and asserts the flag sets match.

Repro env

• Branch: main @ 2ee912d (release v1.21.0)

[Widthdom]

Starting work on this issue on branch fix-issue1525.