Move some from xxx commands to plugin (#7942)

# Description

From nushell 0.8 philosophy:
https://github.com/nushell/nushell.github.io/blob/main/contributor-book/philosophy_0_80.md#core-categories

> The following categories should be moved to plugins:
Uncommon format support

So this pr is trying to move following commands to plugin:
- [X] from eml
- [x] from ics
- [x] from ini
- [x] from vcf

And we can have a new plugin handles for these formatting, currently
it's implemented here:

https://github.com/WindSoilder/nu_plugin_format

The command usage should be the same to original command.

If it's ok, the plugin can support more formats like
[parquet](https://github.com/fdncred/nu_plugin_from_parquet), or [EDN
format](https://github.com/nushell/nushell/issues/6415), or something
else.

Just create a draft pr to show what's the blueprint looks like, and is
it a good direction to move forward?

# User-Facing Changes

_(List of all changes that impact the user experience here. This helps
us keep track of breaking changes.)_

# Tests + Formatting

Don't forget to add tests that cover your changes.

Make sure you've run and fixed any issues with these commands:

- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A
clippy::needless_collect` to check that you're using the standard code
style
- `cargo test --workspace` to check that all tests pass

# After Submitting

If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.

crates/nu_plugin_formats/src/lib.rs

@@ -0,0 +1,55 @@
+mod from;
+
+use from::{eml, ics, ini, vcf};
+use nu_plugin::{EvaluatedCall, LabeledError, Plugin};
+use nu_protocol::{Category, PluginSignature, SyntaxShape, Type, Value};
+
+pub struct FromCmds;
+
+impl Plugin for FromCmds {
+    fn signature(&self) -> Vec<PluginSignature> {
+        vec![
+            PluginSignature::build(eml::CMD_NAME)
+                .input_output_types(vec![(Type::String, Type::Record(vec![]))])
+                .named(
+                    "preview-body",
+                    SyntaxShape::Int,
+                    "How many bytes of the body to preview",
+                    Some('b'),
+                )
+                .plugin_examples(eml::examples())
+                .category(Category::Formats),
+            PluginSignature::build(ics::CMD_NAME)
+                .input_output_types(vec![(Type::String, Type::Table(vec![]))])
+                .plugin_examples(ics::examples())
+                .category(Category::Formats),
+            PluginSignature::build(vcf::CMD_NAME)
+                .input_output_types(vec![(Type::String, Type::Table(vec![]))])
+                .plugin_examples(vcf::examples())
+                .category(Category::Formats),
+            PluginSignature::build(ini::CMD_NAME)
+                .input_output_types(vec![(Type::String, Type::Record(vec![]))])
+                .plugin_examples(ini::examples())
+                .category(Category::Formats),
+        ]
+    }
+
+    fn run(
+        &mut self,
+        name: &str,
+        call: &EvaluatedCall,
+        input: &Value,
+    ) -> Result<Value, LabeledError> {
+        match name {
+            eml::CMD_NAME => eml::from_eml_call(call, input),
+            ics::CMD_NAME => ics::from_ics_call(call, input),
+            vcf::CMD_NAME => vcf::from_vcf_call(call, input),
+            ini::CMD_NAME => ini::from_ini_call(call, input),
+            _ => Err(LabeledError {
+                label: "Plugin call with wrong name signature".into(),
+                msg: "the signature used to call the plugin does not match any name in the plugin signature vector".into(),
+                span: Some(call.head),
+            }),
+        }
+    }
+}