docs: the window size cannot be restored under a tiling compositor

Item 75 shipped claiming the rules window remembers its size. It does
not, and no code here can make it.

Hyprland tiles the window to fill its slot, so the size dragged belongs
to the tile. saveGeometry stores frameGeometry beside normalGeometry and
restoreGeometry restores the normal one, which stays at whatever
resize() last set it to. Decoded from the real state file after a hand
test: frame 2248x806, normal 760x664. The dialog restores 760 correctly
and still opens tiled.

Three diagnoses were tried before this one and each was disproved by a
probe rather than argued away: that restoreGeometry rejected the blob as
off-screen, that the layout overrode a geometry applied before the first
show, and that a test could tell the broken and fixed versions apart.
The last one matters most: the offscreen platform returns an identical
frame for both, so a size assertion passed against the bug and a
mutation restoring it left the suite green. That assertion is not
reinstated.

The column widths, which are what actually works, keep their test. The
changelog and the backlog entry are corrected to say what ships, and
CLAUDE.md gains both the tiling-compositor trap and the rule that the
offscreen platform cannot test window sizing at all.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/CLAUDE.md b/CLAUDE.md
index 107fe28..6ab47b3 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -328,6 +328,25 @@ one route out of three. Assert every route. Underneath sits a second trap:
 `done()`, so a test for the closed path has to `show()` the dialog first or it
 asserts nothing at all.
 
+**Under a tiling compositor a window's size is not the application's to
+restore, and the user's desktop is Hyprland.** `saveGeometry` stores
+`frameGeometry` and `normalGeometry`; `restoreGeometry` restores the NORMAL
+one. When the compositor tiles the window to fill its slot, the size the user
+drags is the tile's, and `normalGeometry` keeps whatever the code last passed to
+`resize()`. Measured against the real state file after a hand test: frame
+2248x806, normal 760x664, so the dialog correctly restored 760 and correctly
+looked broken. A whole session went into "the geometry restore is broken" before
+the blob was decoded. Decode the stored geometry before theorising, and expect
+`maximized` to read as a value no bool should hold, which is the tiled state Qt
+records and does not round-trip.
+
+The corollary for tests: **the offscreen platform cannot test window sizing at
+all.** It prints "This plugin does not support propagateSizeHints()" and returns
+an identical frame for a correct restore and a broken one, verified in a
+standalone program containing none of this project's code. A size assertion
+there passes against both, and a mutation putting the bug back leaves the suite
+green. Assert on the stored value, and leave the frame to a hand test.
+
 **A queued load can outlive the state that started it.** `loadThread` crosses to the worker
 on a queued connection, so its reply lands after whatever the UI did in the meantime. The
 generation counter covers a superseded *query*, not a superseded *selection*: blanking the