feat(analytics): add date range filtering to analytics endpoints usin…

[jikrana1]

Closes #854

Problem description

The analytics endpoints currently process the user's complete history without allowing any date filtering. As the amount of stored history grows, analytics queries become slower and users cannot generate reports for specific periods such as the last 7 days, last 30 days, 90 days, or a custom date range.

Proposed solution

Added optional query parameter support (from, to, last) to the getSummary, getTrends, getBreakdown, and getPersonalSummary endpoints.

Implementation details:

• Created a reusable buildDateFilter helper function to parse and validate from, to, and last.
• Applied strict validation: from/to must be valid dates, last must be a positive integer.
• Return 400 Bad Request with descriptive error messages for invalid combinations.
• Merged the date filters into the $match stage of all 4 aggregation pipelines, ensuring createdAt is filtered efficiently before any grouping occurs.
• Preserved the existing behavior perfectly when no date filters are provided.

Benefits

• ✅ Improves analytics performance by reducing dataset size.
• ✅ Allows users to analyze specific time periods.
• ✅ Makes the analytics API more flexible and user-friendly.

Testing instructions

1. Call /analytics/summary?last=7. It should return stats for the last 7 days.
2. Call /analytics/summary?from=2026-01-01&to=2026-06-30. It should return stats for that specific 6-month range.
3. Call /analytics/summary?last=7&from=2026-01-01. It should return a 400 Bad Request error (cannot combine last with from/to).
4. Call the endpoints without any parameters. They should continue working exactly as before.

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[Userunknown84]

Merge Conflict shown kindly fix this

[Userunknown84]

Merge conflict shown kindly fix this.

[Userunknown84]

Ye part delete h sabhi parts me

[Userunknown84]

@jikrana1 fix the issue then i will merge.