refactor: Update title for octant portfolio health analysis

- Changed the title from "Octant Portfolio Health: Measuring Grant Impact Through Open Data" to "Octant Project Portfolio: Tracking OSS Activity Through Open Data" for improved clarity and focus on OSS activity.

Author: ccerv1

analysis/octant/longitudinal-tracking/octant-portfolio-health.py

@@ -7,7 +7,7 @@
 @app.cell(hide_code=True)
 def _(mo):
     mo.md(r"""
-    # Octant Portfolio Health: Measuring Grant Impact Through Open Data
+    # Octant Project Portfolio: Tracking OSS Activity Through Open Data
     <small>Owner: <span style="background-color: #f0f0f0; padding: 2px 4px; border-radius: 3px;">OSO</span> · Last Updated: <span style="background-color: #f0f0f0; padding: 2px 4px; border-radius: 3px;">2026-01-12</span></small>
     """)
     return