fix(startup): let startup_query name a built-in filter, and run it

Two defects, both reachable only after item 93.

startupSavedQuery() searched the saved queries alone, so a startup_query of
"Inbox" matched nothing once Inbox shipped as a built-in filter and the
duplicated entry was removed from queries.json. It then fell back to
m_savedQueries.first(), which is an arbitrary choice that used to look
reasonable while every install carried an Inbox entry: with the duplicates gone
it opened on a leftover search for one sender, and an empty queries.json opened
on nothing at all. The search now covers the saved queries first, so the user's
own entry wins a name collision, then the built-in filters; the fallback is the
Unread filter, which is always present.

The default startup name has always been "Unread" and now resolves for the
first time: before this it named nothing unless the user happened to have such
an entry.

The constructor also read startup.query directly, and a generated entry stores
no query at all, so even a matching filter opened an empty bar. It resolves
through Config::resolvedQuery() now, unscoped, since the account dropdown
starts on "All accounts".

Icons per the user's choices: a star for Important rather than the flag
action's own icon, since on the query row an icon reads as a category rather
than as an instruction, and mail-folder-sent rather than mail-sent.

Three tests changed rather than adapted, because their premises were the
defect. Two asserted the first-saved-query fallback.
aCronSyncDoesNotRefreshBeforeAnyQueryHasRun assumed a fresh window had run no
query, which is no longer true; it is now
aCronSyncRefreshesTheLastRunQueryNotTheQueryBar and asserts the property that
actually matters on a cron timer, through a new lastRunQueryForTesting() seam,
since a legitimate refresh bumps the generation and the counter cannot tell the
two apart.

1 files changed, 14 insertions, 1 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7b4df18..942fe41 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,10 +14,23 @@ point at which they are stable.
 ### Changed
 
 - The built-in filters carry icons, like the Save button at the other end of
-  the query row, with their text beside them.
+  the query row, with their text beside them. Important is a star, and Sent
+  uses the folder icon rather than the envelope-in-flight some themes lack.
 
 ### Fixed
 
+- **`startup_query` can name a built-in filter**, and looks at both those and
+  your saved queries. In 0.21.0 it searched saved queries only, so a
+  `startup_query = Inbox` stopped matching once the duplicated Inbox entry was
+  removed from `queries.json`, and the application opened on whichever query
+  happened to be first in that file. A name matching nothing now falls back to
+  the Unread filter rather than to an arbitrary saved query, and a saved query
+  still wins a name collision with a filter.
+
+  A `startup_query` naming a filter also **runs**. A filter composes its query
+  from your accounts rather than storing one, and the startup path read the
+  stored field directly, so it would have opened on an empty query bar.
+
 - The flagged filter is labelled **Important**, matching the action of the same
   name. It shipped in 0.21.0 as "Flagged", which put the same tag under two
   names in one window.