bugfix: wrong display of human readable string (#15522)

I think after that we can close  #14790

# Description
So the issue was the tiny time delta between the moment the "date
form-human" command is executed, and the moment the value gets
displayed, using chrono_humanize.

When in inputing "in 30 seconds", we currently get:
```
[crates\nu-protocol\src\value\mod.rs:950:21] HumanTime::from(*val) = HumanTime(
    TimeDelta {
        secs: 29,
        nanos: 992402700,
    },
)```
And with "now":
```
crates\nu-protocol\src\value\mod.rs:950:21] HumanTime::from(*val) =
HumanTime(
    TimeDelta {
        secs: -1,
        nanos: 993393200,
    },
)
```

My solution is to round this timedelta to seconds and pass this to chrono_humanize.
Example: instead of passing (-1s + 993393200ns), we pass 0s.
Example: instead of passing (29s + 992402700ns), we pass 30s


# User-Facing Changes
Before 🔴 
```nushell
~> "in 3 days" | date from-human
Fri, 11 Apr 2025 09:06:36 +0200 (in 2 days)
~> "in 30 seconds" | date from-human
Tue, 8 Apr 2025 09:07:09 +0200 (in 29 seconds)
```

After those changes 🟢 
```nushell
~> "in 3 days" | date from-human
Fri, 11 Apr 2025 09:03:47 +0200 (in 3 days)
~> "in 30 seconds" | date from-human
Tue, 8 Apr 2025 09:04:28 +0200 (in 30 seconds)
```

# Tests + Formatting
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# After Submitting
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crates/nu-command/src/date/from_human.rs

@@ -103,19 +103,21 @@ fn helper(value: Value, head: Span) -> Value {
         }
     };
 
-    if let Ok(date) = from_human_time(&input_val, Local::now().naive_local()) {
+    let now = Local::now();
+
+    if let Ok(date) = from_human_time(&input_val, now.naive_local()) {
         match date {
             ParseResult::Date(date) => {
-                let time = Local::now().time();
+                let time = now.time();
                 let combined = date.and_time(time);
-                let local_offset = *Local::now().offset();
+                let local_offset = *now.offset();
                 let dt_fixed = TimeZone::from_local_datetime(&local_offset, &combined)
                     .single()
                     .unwrap_or_default();
                 return Value::date(dt_fixed, span);
             }
             ParseResult::DateTime(date) => {
-                let local_offset = *Local::now().offset();
+                let local_offset = *now.offset();
                 let dt_fixed = match local_offset.from_local_datetime(&date) {
                     chrono::LocalResult::Single(dt) => dt,
                     chrono::LocalResult::Ambiguous(_, _) => {
@@ -140,9 +142,9 @@ fn helper(value: Value, head: Span) -> Value {
                 return Value::date(dt_fixed, span);
             }
             ParseResult::Time(time) => {
-                let date = Local::now().date_naive();
+                let date = now.date_naive();
                 let combined = date.and_time(time);
-                let local_offset = *Local::now().offset();
+                let local_offset = *now.offset();
                 let dt_fixed = TimeZone::from_local_datetime(&local_offset, &combined)
                     .single()
                     .unwrap_or_default();
@@ -151,19 +153,19 @@ fn helper(value: Value, head: Span) -> Value {
         }
     }
 
-    match from_human_time(&input_val, Local::now().naive_local()) {
+    match from_human_time(&input_val, now.naive_local()) {
         Ok(date) => match date {
             ParseResult::Date(date) => {
-                let time = Local::now().time();
+                let time = now.time();
                 let combined = date.and_time(time);
-                let local_offset = *Local::now().offset();
+                let local_offset = *now.offset();
                 let dt_fixed = TimeZone::from_local_datetime(&local_offset, &combined)
                     .single()
                     .unwrap_or_default();
                 Value::date(dt_fixed, span)
             }
             ParseResult::DateTime(date) => {
-                let local_offset = *Local::now().offset();
+                let local_offset = *now.offset();
                 let dt_fixed = match local_offset.from_local_datetime(&date) {
                     chrono::LocalResult::Single(dt) => dt,
                     chrono::LocalResult::Ambiguous(_, _) => {
@@ -188,9 +190,9 @@ fn helper(value: Value, head: Span) -> Value {
                 Value::date(dt_fixed, span)
             }
             ParseResult::Time(time) => {
-                let date = Local::now().date_naive();
+                let date = now.date_naive();
                 let combined = date.and_time(time);
-                let local_offset = *Local::now().offset();
+                let local_offset = *now.offset();
                 let dt_fixed = TimeZone::from_local_datetime(&local_offset, &combined)
                     .single()
                     .unwrap_or_default();