Merge: searching from the message pane (item 85)

Five surfaces in the message pane offer a search built from what they show:
the header's subject and date, its sender and recipients on a single-message
thread, a tag chip, a body selection, and every header per message in the
details dialog. Each offers Search for this, which replaces the query, and
Add to search, which narrows it.

The details dialog became labelled rows along the way, which the user wanted
independently of this feature.

Hand tested through every surface, including the case the parenthesising
exists for: adding a sender to 'tag:inbox or tag:flagged' narrows it rather
than widening it.

1 files changed, 21 insertions, 0 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3dea47f..7b22d9f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,27 @@ point at which they are stable.
 
 ## [Unreleased]
 
+### Added
+
+- Anything on screen in the message pane can be searched for by right-clicking
+  it. The subject and the date in the header, the sender and recipients when
+  the thread holds one message, a tag chip, a phrase selected in the message
+  body, and every header of every message in the details dialog. Each offers
+  **Search for this**, which replaces the query, and **Add to search**, which
+  narrows what is already there.
+
+  Narrowing is the half worth knowing about: a query returning a thousand
+  threads can be cut down by adding a sender or a date to it, without retyping
+  the query you started from.
+
+  A search is only ever a search. Turning what you find into a tagging rule is
+  still the existing road: save the query, then create a rule from it.
+
+### Changed
+
+- The message details dialog shows labelled rows rather than one block of
+  text, so each value can be searched for on its own.
+
 ## [0.19.0] - 2026-08-14
 
 A saved query can become a tagging rule without retyping it, and a rule can no