Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@CategoriesPanel.c`:
- Around line 39-40: The teardown leaves header->metersCopied true after calling
Header_undoMetersCopy(), so the normal draw path still thinks meters are in
copied state and doesn't merge restored columns; update the teardown to clear
the flag by setting this->header->metersCopied = 0 (or false) immediately after
calling Header_undoMetersCopy(), ensuring Header_undoMetersCopy(this->header) is
invoked then the metersCopied field is reset so the draw/layout logic treats
meters as un-copied.

In `@Header.c`:
- Around line 179-183: The loop that accumulates len currently always adds sizes
of hidden columns when iterating past the last visible column (using variables
drawCol, col, numCols, this->maxColumns, and Vector_size), which double-counts
those entries if metersCopied is true; update the loop condition to skip
counting hidden columns when metersCopied is true (e.g., require &&
!metersCopied in the do/while condition) and apply the same fix to the analogous
block that computes colSettings->len later (lines referenced around drawCol use
at 193-210) so colSettings->len matches the actual serialized entries.
- Around line 98-106: The assert in Header_collapseLayout
(assert(this->metersCopied || currentColumns == this->maxColumns)) is too strict
for new call paths (AvailableMetersPanel / MetersPanel clear metersCopied before
invoking collapse); remove or relax that assertion so collapsing proceeds even
when metersCopied is false. Replace the assert with no-op or a runtime guard
that does not abort (e.g., drop the assert entirely) and let the existing
cleanup loop and xReallocArray behavior run normally so reduced layouts with
empty/hidden columns are collapsed without triggering an assertion failure.

In `@MetersPanel.c`:
- Around line 140-143: The code sets modified/result unconditionally after
calling Vector_moveUp/Vector_moveDown, but those functions are no-ops at list
boundaries; change the logic in the handlers that call
Vector_moveUp/Panel_moveSelectedUp and Vector_moveDown/Panel_moveSelectedDown so
you only set modified = true and result = HANDLED when a real move
occurred—detect this by checking whether the item's index changed (compare the
selected index before and after, or use the move function's boolean return if
available) and only mark modified/handled when the index actually differs; apply
the same fix to the symmetric block around the Vector_moveDown calls (also noted
for lines 152-155).

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Duplicate comments:
In `@MetersPanel.c`:
- Line 9: Move the include of Vector.h so the translation unit's corresponding
header MetersPanel.h is included first (after config.h): either reorder the
includes so MetersPanel.h appears before Vector.h, or remove the Vector.h
include entirely if all Vector symbols are already provided transitively via
MetersPanel.h; also verify any use of Vector types/functions in functions like
those in MetersPanel.c require an explicit include and add Vector.h only if
needed.

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@Header.h`:
- Around line 18-21: Header.h uses the bool type in the Header_ struct
(metersCopied) but doesn't include <stdbool.h>, creating fragile transitive
include dependencies; update Header.h to directly include <stdbool.h> so the
bool definition is explicit for the Header_ struct and any code including
Header.h (referencing Header_, metersCopied, and the Header.h interface) no
longer relies on other headers to provide bool.

In `@MetersPanel.c`:
- Around line 200-203: The condition that sets header->metersCopied to false
currently only runs when (modified || sideMove), which misses style-only edits
(the F4/space path) that also mutate a meter; update the logic so style-only
changes are treated as a real modification—either expand the condition to
include the style-change flag used by the F4/space path (e.g., styleChanged or
whatever symbol marks style edits) or call Header_collapseLayout(header);
header->metersCopied = false unconditionally after any code path that mutates
meter style; key symbols to touch: the conditional around
Header_collapseLayout(header) and header->metersCopied assignment, and the
style-change handler invoked by F4/space.

---

Outside diff comments:
In `@Header.c`:
- Around line 245-277: Header_forEachColumn's draw path now iterates meters in
columns[currentColumns..maxColumns) when !metersCopied, but Header_updateData
still only updates visible columns, so hidden preserved meters keep stale
values; update Header_updateData to mirror the same traversal: when
this->metersCopied is false, iterate drawCol from the current column index
through this->maxColumns (using the same loop condition as Header_forEachColumn)
and process/update each Meter in this->columns[drawCol] (honoring
Meter_isMultiColumn and columnWidthCount logic if relevant), otherwise keep the
existing visible-only behavior; reference Header_forEachColumn,
Header_updateData, this->metersCopied, currentColumns, maxColumns, columns, and
Meter_isMultiColumn to align the traversal and avoid stale meters.

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Outside diff comments:
In `@MetersPanel.c`:
- Around line 121-131: The style-change branch (cases ' ', KEY_F(4), 't')
mutates a meter via Meter_nextSupportedMode/Meter_setMode and updates the list
item with Panel_set/Meter_toListItem but doesn't mark the editor state as
modified; update that branch to set modified = true after applying the mode
change (before result = HANDLED) so Header_collapseLayout and subsequent
collapse logic will run for this mutation.