Delete every knob the fixed profiles cannot honor

The CLI still advertised --model, --steps, --guidance-scale, --device and a
deprecated --auto. Each pinned a value the two surviving profiles fix -- the
model stack, the per-stage distilled schedule, CFG 1.0, CUDA -- so the only
outcome any of them had was an error raised several frames below the caller,
under a message naming an internal profile. A flag whose sole result is a
refusal is worse than no flag: it advertises a capability that does not exist,
and it lets a wrapper thread a value that will silently do nothing. They are
gone from the parser, from InvisibleEngine, and from WatermarkRemover, so the
failure is now a TypeError or a Click "No such option" at the point the caller
can act on.

The install hint was wrong in the same way. is_available() checked torch and
diffusers, then told the user to install [diffusion] -- which contains neither
DiffSynth nor the Z-Image face stage both profiles run. Following the advice
produced a second, different failure. The module list and the extra name now
live once in watermark_profiles (REMOVAL_MODULES, INVISIBLE_EXTRA) and are read
by both the CLI gate and the remover's precondition, which cannot drift apart
because they are the same tuple.

The adaptive-polish default moved out of the argument parser. It was resolved by
reading Click's parameter source, which put per-profile data in the CLI layer,
left the engine declaring the opposite default (False vs True) so a library
caller and a CLI caller on one profile got different output, and lost the polish
entirely for anything that supplies the flag non-interactively. The flag is now
tri-state (default=None) and resolve_adaptive_polish owns the per-profile
answer. The seed follows the same rule: the CLI stopped pre-resolving it.

Dead code removed with it: six scan_*_video wrappers and the _scan_video helper
none of them had a caller for, PNG_METADATA_KEYS, feather_region_composite and
the remover region path that was only reachable from a no-caller convenience
wrapper, remove_watermark_batch on both layers, try_empty_device_cache, the
_generate/_run_qwen_zimage pass-through pair, self.model_id, and the _internal
PEP 562 shim that no caller ever went through. get_device now answers cuda or
cpu only: mps and xpu travelled one frame to the same CUDA-only refusal while
costing a device probe each, and that refusal now names the resolved device, so
device=None on a CUDA-less host says 'cpu' rather than 'None'. The XPU wheel
index went with them.

Docs: README, cli, installation, python-api, supported-signals,
known-limitations and module-internals all still described the removed profiles,
the CPU/MPS/XPU ladder, a `default`->`sdxl` alias, and the wrong extra.
known-limitations still listed the retired SDXL strength ladder as current.
scripts/smoke_matrix.py and real_examples_e2e.py drove --device mps.

Next release is 0.25.0, not a patch: this removes public parameters and
narrows a published extra on top of the released 0.24.0.

pre-commit: 1) maintain.sh - exit 0 (1091 tests, Pyright 0 errors, no
vulnerabilities); 2) /simplify - 4 agents, 11 findings applied, 2 skipped
(dropping the `device` parameter entirely, which raiw-app pins; folding
diffsynth into the `diffusion` extra, which video-only callers do not need);
3) docs sync - grepped every removed identifier across README, docs/, scripts/,
.claude/; updated 9 docs; 4) CLAUDE.md - added the no-error-only-knobs rule to
.claude/rules/development.md

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

docs/cli.md

@@ -20,8 +20,7 @@ defaults. This page focuses on choosing the right command.
 | `visible` and `erase` with OpenCV | `remove-ai-watermarks[visible]` (`pixels` is the minimal runtime) |
 | `visible` or `erase` with MI-GAN | `remove-ai-watermarks[migan]` |
 | `visible` or `erase` with big-LaMa | `remove-ai-watermarks[lama]` |
-| `invisible` | `remove-ai-watermarks[diffusion]` |
-| `invisible --pipeline qwen-zimage` | `remove-ai-watermarks[qwen-zimage]` |
+| `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]` |
@@ -340,10 +339,11 @@ failed encode does not overwrite an existing result.
 
 ## Remove invisible watermarks
 
-Install the diffusion dependencies first:
+Install the removal dependencies first. Both profiles are CUDA-only and both
+run the DiffSynth Z-Image face stage, so this is the extra either one needs:
 
 ```bash
-uv tool install --force "remove-ai-watermarks[diffusion]"
+uv tool install --force "remove-ai-watermarks[qwen-zimage]"
 ```
 
 Then run:
@@ -380,8 +380,11 @@ remove-ai-watermarks invisible image.png -o clean.png \
   --pipeline qwen-zimage --force
 ```
 
-The legacy `default` value is an alias for `sdxl`. The `--auto` option is
-deprecated, emits a warning, and changes nothing.
+There is no `--model`, `--steps`, `--guidance-scale` or `--device` option, and the
+deprecated `--auto` is gone. Each profile pins its model stack, its per-stage
+schedule, CFG 1.0 and CUDA, so every one of those flags existed only to be refused
+several layers down. They are not parsed at all now, which fails at the point the
+user can act on rather than after a model load.
 
 ### Work with limited memory
 
@@ -415,7 +418,7 @@ It is a memory strategy, not a guarantee of better quality.
 The `all` command and the `all` installation extra are separate concepts. The
 command runs every applicable stage. Installing `remove-ai-watermarks[all]`
 makes every production backend available; a smaller installation such as
-`remove-ai-watermarks[visible,diffusion]` can also run the command with fewer
+`remove-ai-watermarks[visible,qwen-zimage]` can also run the command with fewer
 optional backends.
 
 ```bash