feat(charts): visualize repository growth over time

[marcgc21]

Description

Create a chart to visualize the cumulative growth of the repository over time. This can include total lines of code, file count, or number of commits to show how the project has scaled.

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📊 Chart Type

• Line chart (cumulative sum)
• Optional: multiple lines (e.g., LOC, files, commits)

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🧾 Data Requirements

• Source options:
  • GitHub API (e.g., /stats/code_frequency, commit history)
  • Local Git log analysis for LOC/file count
• Fields needed:
  • Date (weekly preferred)
  • Cumulative lines of code
  • (Optional) Number of files, commits

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✅ Tasks

• Collect historical data for LOC (and optionally files, commits)
• Calculate cumulative totals over time
• Generate line chart showing growth
• Add axis labels, units, and legend
• Support export or embedding

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📅 Example Output

X-axis: Date (weekly)
Y-axis: Cumulative lines of code (or files, commits)
Lines: Total LOC, Total files (optional), Total commits (optional)

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✅ Acceptance Criteria

• Growth trends are clearly visualized
• Chart reflects cumulative progression accurately
• Labels and legend are present
• Chart is responsive or exportable