Add RG0043: Warn on files exceeding 1000 lines

[Copilot]

Plan: Add analyzer RG0043 - File should not contain more than 1000 lines

• Explore repository structure and understand analyzer pattern
• Build and test to verify current state
• Add RG0043 diagnostic descriptor in RGDiagnosticAnalyzer.cs
• Implement file line count analyzer using RegisterSyntaxTreeAction
• Register the analyzer in Initialize method
• Add RG0043 to SupportedDiagnostics array
• Create unit tests in new FileShouldNotExceedLineLimitTests.cs (5 tests)
• Update README.md with section 43
• Update AnalyzerReleases.Unshipped.md with RG0043 entry
• Build and test to verify implementation (261 tests passing)
• Run code review (no issues found)
• Run security checks (no alerts)
• Address PR feedback: Enhanced README example with line number visualization

Summary

Successfully implemented RG0043 analyzer that warns when a file exceeds 1000 lines. The analyzer:

• Has Info severity as requested
• Uses Maintainability category
• Includes descriptive message with file name and actual line count
• Has comprehensive test coverage (empty, under limit, at limit, over limit scenarios)
• Documentation added to README.md with improved visualization showing line numbers
• Release tracking updated in AnalyzerReleases.Unshipped.md

All quality checks passed.

Original prompt

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This section details on the original issue you should resolve

<issue_title>New analyzer: file should not contain more than 1000 lines.</issue_title>
<issue_description>Default severity: Info</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes New analyzer: file should not contain more than 1000 lines. #9

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[ronnygunawan]

@copilot

[ronnygunawan]

Let's visualize the line numbers:

// In a file with more than 1000 lines:
// RG0043: File 'LargeClass.cs' contains 1523 lines, which exceeds the maximum recommended limit of 1000 lines
   1 | using System;
   2 | using System.Collection;

1521 |     }
1522 | }
1523 |

[Copilot]

Updated the example with line number visualization as suggested in commit d0b4b9e.

[ronnygunawan]

@copilot LGTM