Add pipeline operators to help (#7449)

# Description

_(Thank you for improving Nushell. Please, check our [contributing
guide](../CONTRIBUTING.md) and talk to the core team before making major
changes.)_

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# User-Facing Changes

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# 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-command/src/core_commands/help_operators.rs

@@ -312,6 +312,24 @@ fn generate_operator_info() -> Vec<OperatorInfo> {
             description: "Checks if one value is true and the other is false.".into(),
             precedence: 45,
         },
+        OperatorInfo {
+            op_type: "Pipeline".into(),
+            operator: "&&".into(),
+            name: "PipelineAnd".into(),
+            description:
+                "Runs the pipeline on the left and, if successful, runs pipeline on the right."
+                    .into(),
+            precedence: 0,
+        },
+        OperatorInfo {
+            op_type: "Pipeline".into(),
+            operator: "||".into(),
+            name: "PipelineOr".into(),
+            description:
+                "Runs the pipeline on the left and, if it failed, runs pipeline on the right."
+                    .into(),
+            precedence: 0,
+        },
     ]
 }