feat: bash completion for the launch selectors

Completes the options, and the account keys after --account, read from the
[account.<key>] sections of the config the application itself reads. Thread
and message ids are deliberately not completed: offering them means querying
the whole notmuch index on every Tab, which on a real Maildir is tens of
thousands of ids nobody would pick from a list anyway.

Installed under share/bash-completion/completions, where bash-completion
loads a command's file on demand by name.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4a9879a..830c09e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -21,6 +21,9 @@ point at which they are stable.
   `--message` accepts a Message-ID with or without its angle brackets. A
   selector that matches nothing is named in the status bar and the window
   keeps the view it had.
+- Bash completion for the options, completing account keys from the config
+  after `--account`. Thread and message ids are not completed, since that
+  would query the whole index on every Tab.
 - A second launch now hands its selectors to the already-running window over a
   local socket and asks it to raise itself, rather than opening a second
   window. One process, and so one notmuch database handle.