macos: pixel attachments, live theming, and a signed app

The AppKit shell now draws what the core renders, follows the theme without a
relaunch, and builds into something you can hand to someone.

- Pixel attachments. Surface.images was dropped on the floor here, so a PDF
  pane showed nothing at all: native_images is now set, pardes_image_s carries
  the geometry the core already clipped, and PardesView keeps one CGImage per
  (serial, page, revision) so scrolling costs a draw and not a decode. Image
  panes get real pixels instead of the petscii fallback.

- Themes take hold live. pardes_tick never advanced the chrome animation, so
  every tagline kept the previous theme's colours until the next launch and
  the 16 ms re-pump spun for the rest of the session. pardes_theme_bg retires
  the hand-agreed #121212 and drives the window background and the titlebar
  appearance; a theme with no background of its own now gets a transparent
  window over an NSVisualEffectView.

- The cell snaps to whole DEVICE pixels rather than whole points. Monaco
  advances 8.4014pt at 14, so ceiling to 9 spaced every column 7.1% wider than
  the face was drawn for.

- The dial is one notch per 10 degrees instead of 20, and a release keeps
  turning in proportion to how hard it was thrown -- ramping up from zero at
  the floor, so a slow twist coasts not a little but not at all.

- A file dropped on the grid is a click plus Look, so it opens beside the pane
  it was dropped on. No drop concept was added to the core.

- The titlebar follows the focused pane: proxy icon, filename, and the dirty
  dot. File.saved_revision is the watermark that last one needed.

- Config (SPC f c) prints the resolved startup config path.

- build.zig assembles, signs and packages the bundle itself; build-app.sh is
  gone. -Dmacos-identity= takes a Developer ID, macos-dmg makes the image, and
  the icon is Glenda.

1 files changed, 243 insertions, 119 deletions

diff --git a/test/macos-snapshots/rotate.golden b/test/macos-snapshots/rotate.golden
index 54f0d217..f0cc1eac 100644
--- a/test/macos-snapshots/rotate.golden
+++ b/test/macos-snapshots/rotate.golden
@@ -1,156 +1,280 @@
-== snap results grid=100x30 cursor=4,8
+== snap results grid=100x30 cursor=4,25
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
 |  /private/tmp/pardes-macos-e2e/rotate/cwd                               New Del
-|
-|  x MARK a
 |  zz
-|  x MARK b
+|  x MARK 14
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 |  zz
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 |  /private/tmp/pardes-macos-e2e/rotate/cwd/+Search                       New Del
-|     1 @p0:2:3-6 x MARK a
-|     2 @p0:4:3-6 x MARK b
-|     3 @p0:6:3-6 x MARK c
-== snap forward grid=100x30 cursor=7,3
+|     1 @p0:3:3-6 x MARK 01
+|     2 @p0:5:3-6 x MARK 02
+|     3 @p0:7:3-6 x MARK 03
+== snap forward grid=100x30 cursor=7,4
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
 |  /private/tmp/pardes-macos-e2e/rotate/cwd                               New Del
 |
-|  x MARK a
+|
+|  x MARK 01
 |  zz
-|  x MARK b
+|  x MARK 02
+|  zz
+|  x MARK 03
+|  zz
+|  x MARK 04
+|  zz
+|  x MARK 05
+|  zz
+|  x MARK 06
+|  zz
+|  x MARK 07
+|  zz
+|  x MARK 08
+|  zz
+|  x MARK 09
+|  zz
+|  x MARK 10
+|  zz
+|  x MARK 11
 |  zz
-|  x MARK c
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 |  /private/tmp/pardes-macos-e2e/rotate/cwd/+Search                       New Del
-|     1 @p0:2:3-6 x MARK a
-|     2 @p0:4:3-6 x MARK b
-|     3 @p0:6:3-6 x MARK c
-== snap forward2 grid=100x30 cursor=7,5
+|     1 @p0:3:3-6 x MARK 01
+|     2 @p0:5:3-6 x MARK 02
+|     3 @p0:7:3-6 x MARK 03
+== snap forward2 grid=100x30 cursor=7,6
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
 |  /private/tmp/pardes-macos-e2e/rotate/cwd                               New Del
 |
-|  x MARK a
+|
+|  x MARK 01
 |  zz
-|  x MARK b
+|  x MARK 02
+|  zz
+|  x MARK 03
+|  zz
+|  x MARK 04
+|  zz
+|  x MARK 05
+|  zz
+|  x MARK 06
+|  zz
+|  x MARK 07
+|  zz
+|  x MARK 08
+|  zz
+|  x MARK 09
+|  zz
+|  x MARK 10
+|  zz
+|  x MARK 11
 |  zz
-|  x MARK c
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 |  /private/tmp/pardes-macos-e2e/rotate/cwd/+Search                       New Del
-|     1 @p0:2:3-6 x MARK a
-|     2 @p0:4:3-6 x MARK b
-|     3 @p0:6:3-6 x MARK c
-== snap back grid=100x30 cursor=7,5
+|     1 @p0:3:3-6 x MARK 01
+|     2 @p0:5:3-6 x MARK 02
+|     3 @p0:7:3-6 x MARK 03
+== snap back grid=100x30 cursor=7,6
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
 |  /private/tmp/pardes-macos-e2e/rotate/cwd                               New Del
 |
-|  x MARK a
+|
+|  x MARK 01
 |  zz
-|  x MARK b
+|  x MARK 02
 |  zz
-|  x MARK c
-|
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+|  x MARK 03
+|  zz
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+|  x MARK 07
+|  zz
+|  x MARK 08
+|  zz
+|  x MARK 09
+|  zz
+|  x MARK 10
+|  zz
+|  x MARK 11
+|  zz
+|  /private/tmp/pardes-macos-e2e/rotate/cwd/+Search                       New Del
+|     1 @p0:3:3-6 x MARK 01
+|     2 @p0:5:3-6 x MARK 02
+|     3 @p0:7:3-6 x MARK 03
+== snap forward_by_key grid=100x30 cursor=7,8
+|New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
+|  /private/tmp/pardes-macos-e2e/rotate/cwd                               New Del
 |
 |
+|  x MARK 01
+|  zz
+|  x MARK 02
+|  zz
+|  x MARK 03
+|  zz
+|  x MARK 04
+|  zz
+|  x MARK 05
+|  zz
+|  x MARK 06
+|  zz
+|  x MARK 07
+|  zz
+|  x MARK 08
+|  zz
+|  x MARK 09
+|  zz
+|  x MARK 10
+|  zz
+|  x MARK 11
+|  zz
+|  /private/tmp/pardes-macos-e2e/rotate/cwd/+Search                       New Del
+|     1 @p0:3:3-6 x MARK 01
+|     2 @p0:5:3-6 x MARK 02
+|     3 @p0:7:3-6 x MARK 03
+== snap placed grid=100x30 cursor=7,8
+|New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
+|  /private/tmp/pardes-macos-e2e/rotate/cwd                               New Del
 |
 |
+|  x MARK 01
+|  zz
+|  x MARK 02
+|  zz
+|  x MARK 03
+|  zz
+|  x MARK 04
+|  zz
+|  x MARK 05
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+|  x MARK 07
+|  zz
+|  x MARK 08
+|  zz
+|  x MARK 09
+|  zz
+|  x MARK 10
+|  zz
+|  x MARK 11
+|  zz
+|  /private/tmp/pardes-macos-e2e/rotate/cwd/+Search                       New Del
+|     1 @p0:3:3-6 x MARK 01
+|     2 @p0:5:3-6 x MARK 02
+|     3 @p0:7:3-6 x MARK 03
+== snap placed_released grid=100x30 cursor=7,8
+|New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
+|  /private/tmp/pardes-macos-e2e/rotate/cwd                               New Del
 |
 |
+|  x MARK 01
+|  zz
+|  x MARK 02
+|  zz
+|  x MARK 03
+|  zz
+|  x MARK 04
+|  zz
+|  x MARK 05
+|  zz
+|  x MARK 06
+|  zz
+|  x MARK 07
+|  zz
+|  x MARK 08
+|  zz
+|  x MARK 09
+|  zz
+|  x MARK 10
+|  zz
+|  x MARK 11
+|  zz
+|  /private/tmp/pardes-macos-e2e/rotate/cwd/+Search                       New Del
+|     1 @p0:3:3-6 x MARK 01
+|     2 @p0:5:3-6 x MARK 02
+|     3 @p0:7:3-6 x MARK 03
+== snap thrown grid=100x30 cursor=7,16
+|New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
+|  /private/tmp/pardes-macos-e2e/rotate/cwd                               New Del
 |
 |
+|  x MARK 01
+|  zz
+|  x MARK 02
+|  zz
+|  x MARK 03
+|  zz
+|  x MARK 04
+|  zz
+|  x MARK 05
+|  zz
+|  x MARK 06
+|  zz
+|  x MARK 07
+|  zz
+|  x MARK 08
+|  zz
+|  x MARK 09
+|  zz
+|  x MARK 10
+|  zz
+|  x MARK 11
+|  zz
 |  /private/tmp/pardes-macos-e2e/rotate/cwd/+Search                       New Del
-|     1 @p0:2:3-6 x MARK a
-|     2 @p0:4:3-6 x MARK b
-|     3 @p0:6:3-6 x MARK c
-== snap forward_by_key grid=100x30 cursor=7,7
+|     5 @p0:11:3-6 x MARK 05
+|     6 @p0:13:3-6 x MARK 06
+|     7 @p0:15:3-6 x MARK 07
+== snap thrown_coasted grid=100x30 cursor=7,22
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
 |  /private/tmp/pardes-macos-e2e/rotate/cwd                               New Del
-|
-|  x MARK a
+|  x MARK 07
 |  zz
-|  x MARK b
+|  x MARK 08
+|  zz
+|  x MARK 09
+|  zz
+|  x MARK 10
+|  zz
+|  x MARK 11
+|  zz
+|  x MARK 12
+|  zz
+|  x MARK 13
+|  zz
+|  x MARK 14
+|  zz
+|  x MARK 15
+|  zz
+|  x MARK 16
+|  zz
+|  x MARK 17
+|  zz
+|  x MARK 18
 |  zz
-|  x MARK c
-|
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 |  /private/tmp/pardes-macos-e2e/rotate/cwd/+Search                       New Del
-|     1 @p0:2:3-6 x MARK a
-|     2 @p0:4:3-6 x MARK b
-|     3 @p0:6:3-6 x MARK c
-== draw rotate 900x510 nonblank
+|    15 @p0:31:3-6 x MARK 15
+|    16 @p0:33:3-6 x MARK 16
+|    17 @p0:35:3-6 x MARK 17
+== draw rotate 850x495 nonblank