chore: remove last min trim logic in uplotScaleBuilder (#12627)

<!--A few plain bullets saying what changed and why, for a reviewer
skimming it - not a wall of text, not a restatement of the diff, not
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#### Description

- `UPlotScaleBuilder` was overriding the x-axis max with `endTime - 1
minute`, rounded down to the minute — behaviour carried over from the
legacy `getXAxisScale`.
- On short time windows the trimmed max lands at or before the min, so
the scale range is empty/inverted and the chart draws no data.
- Removes the trim so the requested `min`/`max` pass through as-is and
the scale always matches the selected time range.
- Updates the scale builder tests, including a case for a sub-minute
window.

<!--Reference issues using `Closes #issue-number` to enable automatic
closure on merge. -->
#### Issues closed by this PR
Closes -
https://github.com/orgs/SigNoz/projects/39/views/20?pane=issue&itemId=231774376&issue=SigNoz%7Cengineering-pod%7C5902

<!--If applicable, include screenshots or screen recordings that clearly
show the behavior before the change and the result after the change. -->
#### Screenshots / Screen Recordings

Before - 



https://github.com/user-attachments/assets/11ca2fa4-9a07-42eb-9d8d-3a42daf4cfe1


Now - 




https://github.com/user-attachments/assets/0114fccd-a6ef-4717-8d1c-aa3faf820da7





#### Additional Information

- Only the uPlotV2 path changes

---------

Co-authored-by: Gaurav Tewari <tewarig@users.noreply.github.com>

frontend/src/lib/uPlotV2/config/UPlotScaleBuilder.ts

@@ -56,17 +56,6 @@ export class UPlotScaleBuilder extends ConfigBuilder<
 				maxTime = fallbackMax;
 			}
 
-			// Align max time to "endTime - 1 minute", rounded down to minute precision
-			// This matches legacy getXAxisScale behavior and avoids empty space at the right edge
-			const oneMinuteAgoTimestamp = (maxTime - 60) * 1000;
-			const currentDate = new Date(oneMinuteAgoTimestamp);
-
-			currentDate.setSeconds(0);
-			currentDate.setMilliseconds(0);
-
-			const unixTimestampSeconds = Math.floor(currentDate.getTime() / 1000);
-			maxTime = unixTimestampSeconds;
-
 			return {
 				[scaleKey]: {
 					time: true,

frontend/src/lib/uPlotV2/config/__tests__/UPlotScaleBuilder.test.ts

@@ -44,7 +44,7 @@ describe('UPlotScaleBuilder', () => {
 		expect(adjustSpy).toHaveBeenCalledWith(null, null, undefined, undefined);
 	});
 
-	it('handles time scales using explicit min/max and rounds max down to the previous minute', () => {
+	it('handles time scales using explicit min/max', () => {
 		const min = 1_700_000_000; // seconds
 		const max = 1_700_000_600; // seconds
 
@@ -62,21 +62,25 @@ describe('UPlotScaleBuilder', () => {
 
 		expect(xScale.time).toBe(true);
 		expect(xScale.auto).toBe(false);
-		expect(Array.isArray(xScale.range)).toBe(true);
+		expect(xScale.range).toStrictEqual([min, max]);
+	});
 
-		const [resolvedMin, resolvedMax] = xScale.range as [number, number];
+	it('keeps short time windows intact', () => {
+		const min = 1_786_527_160;
+		const max = 1_786_527_183;
 
-		// min is passed through
-		expect(resolvedMin).toBe(min);
+		const builder = new UPlotScaleBuilder(
+			createScaleProps({
+				scaleKey: 'x',
+				time: true,
+				min,
+				max,
+			}),
+		);
 
-		// max is coerced to "endTime - 1 minute" and rounded down to minute precision
-		const oneMinuteAgoTimestamp = (max - 60) * 1000;
-		const currentDate = new Date(oneMinuteAgoTimestamp);
-		currentDate.setSeconds(0);
-		currentDate.setMilliseconds(0);
-		const expectedMax = Math.floor(currentDate.getTime() / 1000);
+		const config = builder.getConfig();
 
-		expect(resolvedMax).toBe(expectedMax);
+		expect(config.x.range).toStrictEqual([min, max]);
 	});
 
 	it('falls back to getFallbackMinMaxTimeStamp when time scale has no min/max', () => {
@@ -99,9 +103,7 @@ describe('UPlotScaleBuilder', () => {
 
 		expect(getFallbackMinMaxSpy).toHaveBeenCalled();
 		expect(resolvedMin).toBe(100);
-		// max is aligned to "fallbackMax - 60 seconds" minute boundary
-		expect(resolvedMax).toBeLessThanOrEqual(200);
-		expect(resolvedMax).toBeGreaterThan(100);
+		expect(resolvedMax).toBe(200);
 	});
 
 	it('pipes limits through soft-limit adjustment and log-scale normalization before range config', () => {