Give all models a standard JSON with all data, and use a node to load all. (example node included)

### Feature Idea

I would like to make a proposal to professionalize model management.
All models should have a standard JSON with all there specification and most important basic parameters, including suitable CLIP and VAE combinations (or triggers etc). And loader Nodes can use the data directly from the JSON.
Likewise all default values such as CFG, steps, and so on, should be included in this JSON.
All JSON are in the same place like the models, with extension ".json"

models\checkpoints\SDXL\sd_xl_base_1.0.safetensors
models\checkpoints\SDXL\sd_xl_base_1.0.safetensors.json

**!!! ATTENTION: the code here is still in development and most likely contains errors !!!**

At the moment, it is very tedious to define the combinations and basic parameters for various models. It is laborious manual work.

A model loader node load all models and, at the same time output all important parameters as output slots. Likewise there would be a slot with a JSON_MODEL. This output could later be used as an input for various other things, and they could all retrieve the information they need directly from the JSON.

The new node makes it possible to go through all models via a "stepper" and, for example, test prompts on all models without manual changes are possible.
A helper node even makes it possible to adjust weight ranges in the prompt texts. "(prompt text:4)" calculated down to for example 1.25, set by "togen_weight_limit".

ComfyUI could generally ship all supported models with such a JSON, and it could become good practice for ComfyUI to generally expect a JSON for all models and also automatically create it with the basic parameters if it is missing.

All models have a sha256, to find them in case they are moved in directories, or if they are renamed (form "model" to something more useful).

! Spend some effort to define the standard JSON completely and correctly. The included ones are in development.

I am deliberately not making a repository out of the project. I hope the idea will be well received and adopted into ComfyUI.
Nodes: test workflow as well as JSON for a known model are attached. Move them there where the models are.

### Existing Solutions

[smart_model_combo_loader.zip](https://github.com/user-attachments/files/27216146/smart_model_combo_loader.zip)

### Other

_No response_

Review the attached smart_model_combo_loader.zip, test workflow, and known-model JSON to understand the proposed model metadata and node behavior. Compare the proposal with ComfyUI's existing model-loading and node systems. Done would require an agreed standard JSON format, loader-node behavior, and a validated implementation for model discovery and metadata outputs.

Written by the indexing model from the issue text.