[RNTuple] support more types in RNTuple writing

[Moelf]

support writing a single, not too long column of type:

julia> [Float64, Float32, Float16, Int64, Int32, Int16, Int8, UInt64, UInt32, UInt16]

Further reduce amount of hard-coding in writing logic

[codecov]

Codecov Report

Attention: Patch coverage is 83.67347% with 8 lines in your changes missing coverage. Please review.

Project coverage is 84.90%. Comparing base (8a28452) to head (1fe82b1).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/RNTuple/Writing/page_writing.jl	76.47%	8 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #348      +/-   ##
==========================================
+ Coverage   84.79%   84.90%   +0.10%     
==========================================
  Files          20       21       +1     
  Lines        2967     2994      +27     
==========================================
+ Hits         2516     2542      +26     
- Misses        451      452       +1     

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