.aep import: map the Cryptomatte plug-in to EffectCraft's Cryptomatte (#3109)

* AEP import: map the Cryptomatte plug-in to EffectCraft's Cryptomatte

The importer reported every instance of the free Cryptomatte plug-in
(match name `Cryptomatte`) as a lost effect. It now becomes
`ec.3d.cryptomatte`:

- CryptomatteData decodes the plug-in's Settings data (its own
  little-endian layout, documented in docs/aep-format.md 3.7): the
  Cryptomatte layer name and the selection text, both carried verbatim.
- Output maps to Display / Matte Only (Colors -> Colors, Matted RGBA ->
  Matte, Matte Only -> Matte Only). Matted Colors, Selection Mode when on,
  keys or expressions and anything else stored are reported, and
  unreadable data is reported as damaged.
- EffectCraft's Cryptomatte gains a Layer Name text parameter. A layer the
  footage has under exactly that name wins; otherwise the Layer popup
  decides as before. The CPU, GPU and pick paths share one resolver
  (AuxChannels::resolve_crypto_layer_named). Without it, plug-in layer
  names such as Crypto_Material would silently fall back to the first
  layer.

On a real production project this takes the effect losses from 132 to 44.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* AEP import: check Cryptomatte against an After Effects 2026 sample of our own

A sample made in After Effects 2026 (plug-in 2.6.6: a fresh effect,
Selection Mode on, each Output item, with read-backs and renders)
corrected three points of the mapping:

- Selection Mode on was dropped silently: After Effects writes it as a
  default-state record (tdsb 3) holding 1, which the general reader does
  not take. The Cryptomatte step reads that record itself and reports it.
- No Output record is now the plug-in's default Colors, also for an
  instance that borrows the project's definition (every instance after
  the first), which was reported as having no reliable default and fell
  back to EffectCraft's Preview. Keyed or unreadable Output values fall
  back to Colors too, still reported.
- Matted Colors imports as Display Matte (the same matte over the layer's
  own colours) instead of Preview, still reported as an approximation.

docs/aep-format.md 3.7 gets the sampled Output default, the tdsb 3
Selection Mode record and the real fresh Settings data (an empty text of
length 1 and its MurmurHash3, twice, not cry1 and zeros); docs/aep-import.md
the render comparison with After Effects (Matted RGBA matches; Matte Only
differs in alpha; Colors with no layer chosen shows another layer).
Tests: the exact fresh Settings bytes, tdsb 3 Selection Mode, borrowed
definitions, and an opt-in test against the sample once it is in the
corpus (aep/cryptomatte.aep, ignored until the corpus pin includes it).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* AEP import: write Cryptomatte's popup items in the test as After Effects does

The injected Cryptomatte definition wrote `pdnm` and `fnam` as `LIST`
chunks. After Effects writes them as plain chunks whose body is chunks
(`NESTED_IDS`), and the reader only looks there, so the tests never read
Output's item names: they passed through the fallback for a definition
with four items and no `pdnm`, which uses the plug-in's own list.

The harness now writes both as After Effects does. New tests check that
the injected definition reads back with its items and instance name,
that Output is mapped by the item the stored index names (items in
another order, case, an unknown item), and that the fallback without a
`pdnm` still works. With the old `LIST` form, or with the mapping
ignoring the items, the new tests fail.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* AEP import: check Cryptomatte's layer and selection against presets of our own

The After Effects 2026 sample 1400 now has two preset compositions that choose a layer and
pick one object (box_red on CryptoObject) or one material (mat_paint on CryptoMaterial).
CryptomatteData reads both as they are; the picked tokens are the EXR manifest's hashes,
which EffectCraft's selection grammar reads the same as the names.

- The u32 at 108 is MurmurHash3 of the selection text with its NUL (three texts).
- A unit test pins the 127-byte preset data; the sample test now covers all eight
  compositions with their layer and selection.
- Render check: EffectCraft's matte covers exactly the pixels After Effects draws as
  selected, edge coverage within 0.0002. docs/aep-format.md 3.7 and docs/aep-import.md.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Cryptomatte import: report damaged Settings and Selection Mode records

Review follow-ups for #3109:
- CryptomatteData refuses a selection text without its NUL and checks the zero byte
  at 112 for an empty text too.
- A Settings record without its data, and a Selection Mode record whose value cannot
  be read, are reported as damaged data, not taken as the default.
- Layer Name is the effect's last parameter, so the earlier parameters keep their
  indexes and upgraded instances have the same order as new ones.
- A Cryptomatte layer name is matched as given before it is trimmed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Cryptomatte settings: require the selection's NUL to end its declared length

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Cryptomatte: match rank planes by the exact layer name

crypto_rank_planes looked planes up with a case-insensitive whole-name match, so
layers Crypto_A and crypto_a shared planes. The layer prefix now matches
case-sensitively; component letters still match in either case.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

* Format

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

* AEP: the exporter knows Extra::Cryptomatte; rustfmt

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: FredApps <153173854+FredApps@users.noreply.github.com>

docs/aep-format.md

@@ -573,6 +573,43 @@ suffix is a parameter id, not the `parT` position (Curves -0002 Channel before -
 -0005 Quality before -0004). API: `CurvesData`, `MeshData`, `curve_lut`. [V; details: corpus FORMAT
 S]
 
+**Cryptomatte plug-in** (match name `Cryptomatte`, the free Cryptomatte plug-in, 2.6.6 in our
+sample; read from 88 instances in one production project, not made by us, and from our own After
+Effects 2026 sample 1400 (corpus `aep/cryptomatte.aep`: a fresh instance, Selection Mode on, each
+Output item, and two presets of our own that choose a layer and pick one object or material in the
+plug-in's UI; scripting read-backs and renders per composition); H for what neither varies):
+`parT` 0 the input layer; 1 Settings: **arbitrary data** (type 11, `Cryptomatte-0001`, a record and
+`aRbs` / `aRbp` in every instance); 2 Output: popup (Colors, Matted Colors, Matted RGBA, Matte
+Only), **`pard` default 1 = Colors** (bytes 56..64 `00000001 0004 0001`, in the instance's own and
+the project's shared definition; scripting reads 1 from a fresh effect: 1400 `crypto-00-defaults`),
+a written record (`tdsb` 1) holding the item number when set (1400: 2, 3, 4; production: 3 in 81,
+4 in 7); 3 Selection Mode: checkbox (`pdnm` `fnord!`), no record when off, and when on **a
+default-state record (`tdsb` 3) holding 1.0** that After Effects reads back as on and renders
+(1400 `crypto-01-set-all`, `crypto-02-chk-toggled`; the general reader takes only `tdsb` 1
+values, so the importer reads this one itself); the built-in entry. As in every project, only the
+first instance has its own `parT`; the others borrow the project's (1400). The Settings data is
+the plug-in's own layout, **little-endian**: `cry1`; bytes 4..32 differ between instances with
+the same settings (zeros in one, pointer-like values in others: not read); the layer name at 32,
+NUL-padded to 64 bytes (`CryptoObject`, `CryptoMaterial` in 1400: the EXR layer's name, which is
+also its channel prefix there, so the sample cannot tell which of the two the plug-in stores); at
+96 a `u32` 1 and a `u32` that is the same in every instance; at 104 the `u32` length of the
+selection text including its NUL; at 108 **the MurmurHash3 (x86, 32-bit, seed 0) of the selection
+text with its NUL** (V on the three texts of 1400: `<11a97486>` `0x27880767`, `<a5deeb9e>`
+`0xf7374a5b`, the empty text `0x514e28b7`; not read); a zero byte at 112; the selection text from
+113, the matte list as comma-and-space separated ID hashes `<11a97486>, <deadbeef>` (303 tokens in
+production, all in that form). Each token is the 8-digit hash of a picked name as the EXR's
+manifest lists it, i.e. the MurmurHash3 of the name (1400: `box_red` `11a97486` picked on
+CryptoObject, `mat_paint` `a5deeb9e` on CryptoMaterial). After the text 2 to 3 bytes, zeros or
+left-overs of a longer earlier text (1400's presets: 127 bytes, three zeros after the text). **A fresh effect** (the `parT`
+default and the record alike, 116 bytes, 1400) is `cry1`, zeros to 96, then `u32`s 1,
+`0x514e28b7`, 1, `0x514e28b7` and four zero bytes: no layer and an empty text (length 1, its NUL).
+`0x514e28b7` is the hash of a single NUL byte, so the `u32` at 100 looks like the hash of a first
+text that is empty in every sample, its length the `u32` 1 at 96 and its NUL the zero byte at 112
+(H: one value). Layer and selection decode the same in the production project and in 1400's two
+presets, and After Effects draws exactly the picked objects as selected (`crypto-06`: the box,
+`crypto-07`: box and disc, the two objects of `mat_paint`). API: `CryptomatteData` (refuses data without `cry1`, a length past the end or
+a non-zero byte at 112).
+
 ### 3.8 Masks and bezier paths (`tdgp[ADBE Mask Parade]`)
 
 | Field | Chunk path | Offset | Type | Meaning | Evidence | Conf. |