[P] ColQwen3.5-v3 release + Case study

Happy to share the latest colqwen3.5-4.5B model in the series. ColQwen3.5-4.5B-v3 is (avg) on the MTEB ViDoRe leaderboard (Pending release) at 75.67 mean, ~half the params, ~13x fewer embedding dims, ~half the memory footprint of the previous model. Thoughts: V3 edges out v2 on V3 English u (0.6034 vs 0.6023), a marginal gain for substantially compute. The real win was the V2 benchmark jump and surpassing 8B models on V3. That's where I decided to draw the line between further optimization and accepting the limitations of the model and.