#3535: Warp Stabilizer and 3D Camera Tracker keys cover a precomp's contents

On a precomp layer the key covered only the nested comp's size, rate and
duration, so an edit inside the precomp kept a stale analysis. The key now
writes the precomp layer's Essential Properties and what its comp draws, field
by field and recursively. Each comp is written once per key and nesting is
capped, so shared, deep or cyclic precomps are keyed in bounded time. Docs say
what clears an analysis.

docs/agents.md

@@ -492,8 +492,9 @@ between the layer's In and Out points in the background ("Analyzing in backgroun
 then "Stabilizing..."; `warp.status` reports `progress`, `banner`, whether the effect is
 `analyzed`, and the current frame's `warp` matrix, `autoScale` and `crop`); `warp.cancel` stops it
 without writing anything. The analysis is stored in the effect (saved with the project) and is
-one undo step; trimming, slipping, time-remapping or replacing the layer's source clears it and
-the app re-analyses automatically (headless: run `warp.analyze` again). Settings are ordinary
+one undo step; trimming, slipping, time-remapping or replacing the layer's source, editing its
+masks, the effects above the Warp Stabilizer or, on a precomp layer, the precomp's contents
+clears it and the app re-analyses automatically (headless: run `warp.analyze` again). Settings are ordinary
 properties under the instance's groups, e.g. `effects/#1/stabilization/result` (0 Smooth Motion,
 1 No Motion), `effects/#1/stabilization/smoothness`, `effects/#1/stabilization/method`,
 `effects/#1/borders/framing` (0 Stabilize Only … 3 Stabilize, Synthesize Edges),
@@ -540,7 +541,8 @@ Each edit is one undo step; the first create adds the one-node "3D Tracker Camer
 startFrame?: 1, includePoints?: true}` exports the solve as an executable Blender scene script:
 baked camera/lens/focus, synced video background, points and ground. See
 [Blender camera export](blender-camera-export.md) for framing, assumptions and limitations.
-Changing the layer's frames clears the analysis; changing `effects/#1/shotType`,
+Changing the layer's frames, masks, the effects above the tracker or a precomp's contents
+clears the analysis; changing `effects/#1/shotType`,
 `effects/#1/horizontalAngleOfView`, `effects/#1/advanced/solveMethod` re-solves the stored tracks.
 
 ```sh