Verify every doc claim against the source and fix what drifted

Every code-referencing claim in the docs, the README and the rules files was
checked against src/, and each finding was re-derived independently before it
was applied. 35 held, 5 were false positives.

Two of them were code, not text. `InvisibleOptions` promises in its docstring to
mirror `InvisibleEngine`, and two defaults had silently stopped:
`max_resolution=None` reached `_target_size`'s `max_resolution > 0` and raised
`TypeError` on every library call that left the options alone, and
`cpu_offload=True` made a library run slower than the identical CLI run. Both are
fixed, and `TestInvisibleOptionsMirrorTheEngine` compares the two signatures
field by field rather than pinning the two values that happen to be known. A
companion assertion in `TestTargetSize` reads the engine's own declared default,
so a drift on the engine side -- which the mirror check alone would accept,
because both sides would still agree -- fails too.

The user-facing docs: README called `invisible` GPU-optional where it raises
without CUDA, and gave the image `metadata` command `video metadata`'s output
rule, promising the source survives a command that overwrites it. Yuanbao was
missing from the supported-mark list. `veo` was listed among the video policies
that require a run anchor, though its row sets no `anchor_iou`.
`known-limitations` called ControlNet the default profile and contradicted
itself ninety lines below. An unescaped pipe truncated the `hailuo` table row.
The `dev` extra, the CI shape, ffmpeg's role, the sdist boundary and the
strength-curve range were corrected, and `remove_all`/`remove_batch`, the pill
gate, `erase --keep-metadata` and `all`'s CUDA failure mode were documented.

Research notes that described removed modules, extras and flags in the present
tense now say so once in the page banner instead of sentence by sentence, which
covers the whole page rather than the lines that happened to be noticed, and one
fixture is referred to by role rather than by name.

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

docs/cli.md

@@ -22,8 +22,9 @@ defaults. This page focuses on choosing the right command.
 | `visible` or `erase` with big-LaMa | `remove-ai-watermarks[lama]` |
 | `invisible` and `all` (needs CUDA) | `remove-ai-watermarks[qwen-zimage]` |
 | `video metadata` and `video identify --no-visible` | Default package |
-| `video identify`, `video visible`, and visible/all batch modes | `remove-ai-watermarks[video]` |
-| `video invisible` and `video all --invisible` | `remove-ai-watermarks[video,diffusion]` |
+| `video identify` | `remove-ai-watermarks[video]` |
+| `video visible`, `video all`, and visible/all batch modes | `remove-ai-watermarks[video]` plus ffmpeg on PATH |
+| `video invisible` and `video all --invisible` | `remove-ai-watermarks[video,diffusion]` plus ffmpeg on PATH |
 | HEIC/HEIF/AVIF pixel input | Add `remove-ai-watermarks[heif]` |
 | Every production command and backend | `remove-ai-watermarks[all]` |
 
@@ -67,7 +68,8 @@ remove-ai-watermarks visible image.png -o clean.png
 The default behavior:
 
 - checks every registered visible mark;
-- removes every detected match;
+- removes every detected match, except the weakly detected Jimeng label pill,
+  which needs corroboration (see [supported signals](supported-signals.md));
 - selects the best installed fill backend;
 - strips AI metadata from the output.
 
@@ -132,7 +134,8 @@ Two more knobs tune the fill. `--dilate N` (default 3) grows every box by `N`
 pixels before inpainting, which helps when a mark has a soft edge or a drop
 shadow just outside the box you measured; it applies to every backend because it
 shapes the mask. `--inpaint-method telea|ns` selects the classical algorithm and
-only affects the `cv2` backend.
+only affects the `cv2` backend. Like `visible`, `erase` strips AI metadata from
+the output by default; pass `--keep-metadata` to retain it.
 
 ## Strip AI metadata
 
@@ -439,10 +442,16 @@ The command runs:
 
 The visible options and diffusion options are also available on `all`.
 
-If invisible removal is required but the `qwen-zimage` extra is unavailable, `all` still
-writes the result of the visible and metadata stages, prints a prominent
-warning, and exits with code 1. This prevents a partial result from being
-reported as complete.
+When the `qwen-zimage` extra is unavailable, `all` still writes the result of
+the visible and metadata stages, prints a prominent warning, and exits with code
+1. That happens on every run without the extra: the skipped stage is what would
+have decided whether a signal was there. This prevents a partial result from
+being reported as complete.
+
+If the extra is installed but the machine has no CUDA, which is the usual macOS
+case, the run fails at engine construction instead: `all` prints
+`Error: Invisible-watermark removal is CUDA-only ...`, writes no output at all,
+and exits with code 1.
 
 ## Process a directory