feat: high-level implementations for Positional Embeddings

[avik-pal]

• Move Embedding into a different File
• Rotary Position Embedding (RoPE)
  • Implementation
  • Tests
  • Documentation
• Sinusoidal Positional Embedding
  • Implementation
  • Tests
  • Documentation

[github-actions]

Benchmark Results (ASV)

	main	9c7c15c...	main/9c7c15caaf91e0...
basics/overhead	0.129 ± 0.0015 μs	0.14 ± 0.0024 μs	0.925
time_to_load	0.914 ± 0.015 s	0.913 ± 0.0086 s	1

Benchmark Plots

A plot of the benchmark results have been uploaded as an artifact to the workflow run for this PR.
Go to "Actions"->"Benchmark a pull request"->[the most recent run]->"Artifacts" (at the bottom).

[codecov]

Codecov Report

Attention: Patch coverage is 44.92754% with 38 lines in your changes missing coverage. Please review.

Project coverage is 74.37%. Comparing base (73816b6) to head (9c7c15c).

Files with missing lines	Patch %	Lines
src/layers/embedding.jl	44.92%	38 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (73816b6) and HEAD (9c7c15c). Click for more details.

HEAD has 27 uploads less than BASE

Flag	BASE (73816b6)	HEAD (9c7c15c)
	51	24

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1237       +/-   ##
===========================================
- Coverage   85.30%   74.37%   -10.94%     
===========================================
  Files         153      152        -1     
  Lines        6317     6330       +13     
===========================================
- Hits         5389     4708      -681     
- Misses        928     1622      +694     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.