Test command names and search terms for redundancy (#6380)

* Test commands for proper names and search terms

Assert that the `Command.name()` is equal to `Signature.name`

Check that search terms are not just substrings of the command name as
they would not help finding the command.

* Clean up search terms

Remove redundant terms that just replicate the command name.
Try to eliminate substring between search terms, clean up where
necessary.

crates/nu-command/src/date/date_.rs

@@ -23,7 +23,6 @@ impl Command for Date {
 
     fn search_terms(&self) -> Vec<&str> {
         vec![
-            "date",
             "time",
             "now",
             "today",

crates/nu-command/src/date/format.rs

@@ -35,7 +35,7 @@ impl Command for SubCommand {
     }
 
     fn search_terms(&self) -> Vec<&str> {
-        vec!["date", "format", "strftime"]
+        vec!["fmt", "strftime"]
     }
 
     fn run(

crates/nu-command/src/date/humanize.rs

@@ -22,8 +22,6 @@ impl Command for SubCommand {
 
     fn search_terms(&self) -> Vec<&str> {
         vec![
-            "date",
-            "humanize",
             "relative",
             "now",
             "today",

crates/nu-command/src/date/list_timezone.rs

@@ -22,7 +22,7 @@ impl Command for SubCommand {
     }
 
     fn search_terms(&self) -> Vec<&str> {
-        vec!["UTC", "GMT", "timezone", "list", "list-timezone"]
+        vec!["UTC", "GMT", "tz"]
     }
 
     fn run(

crates/nu-command/src/date/now.rs

@@ -19,7 +19,7 @@ impl Command for SubCommand {
     }
 
     fn search_terms(&self) -> Vec<&str> {
-        vec!["date", "now", "present", "current-time"]
+        vec!["present", "current-time"]
     }
 
     fn run(

crates/nu-command/src/date/to_record.rs

@@ -23,7 +23,7 @@ impl Command for SubCommand {
     }
 
     fn search_terms(&self) -> Vec<&str> {
-        vec!["date", "to", "record", "structured", "table"]
+        vec!["structured", "table"]
     }
 
     fn run(

crates/nu-command/src/date/to_table.rs

@@ -23,7 +23,7 @@ impl Command for SubCommand {
     }
 
     fn search_terms(&self) -> Vec<&str> {
-        vec!["date", "to", "record", "structured", "table"]
+        vec!["structured"]
     }
 
     fn run(

crates/nu-command/src/date/to_timezone.rs

@@ -34,9 +34,7 @@ impl Command for SubCommand {
 
     fn search_terms(&self) -> Vec<&str> {
         vec![
-            "date",
-            "to",
-            "timezone",
+            "tz",
             "transform",
             "convert",
             "UTC",