feat: Flotilla stage redesign

[colin-ho]

Changes Made

Add tentative redesign (and comment for rationale) for stages, subject to change.

Related Issues

Checklist

• Documented in API Docs (if applicable)
• Documented in User Guide (if applicable)
• If adding a new documentation page, doc is added to docs/mkdocs.yml navigation
• Documentation builds and is formatted properly (tag @/ccmao1130 for docs review)

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 195 lines in your changes missing coverage. Please review.

Project coverage is 78.19%. Comparing base (398d79c) to head (97be2c2).
Report is 6 commits behind head on main.

Files with missing lines	Patch %	Lines
src/daft-distributed/src/stage/stage_builder.rs	0.00%	147 Missing ⚠️
src/daft-distributed/src/stage/mod.rs	0.00%	27 Missing ⚠️
src/daft-distributed/src/plan/mod.rs	0.00%	14 Missing ⚠️
src/daft-distributed/src/pipeline_node/mod.rs	0.00%	2 Missing ⚠️
src/daft-distributed/src/pipeline_node/collect.rs	0.00%	1 Missing ⚠️
src/daft-distributed/src/pipeline_node/limit.rs	0.00%	1 Missing ⚠️
...rc/daft-distributed/src/pipeline_node/translate.rs	0.00%	1 Missing ⚠️
src/daft-distributed/src/python/mod.rs	0.00%	1 Missing ⚠️
src/daft-distributed/src/scheduling/dispatcher.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4306      +/-   ##
==========================================
+ Coverage   77.76%   78.19%   +0.42%     
==========================================
  Files         819      811       -8     
  Lines      107259   107273      +14     
==========================================
+ Hits        83405    83877     +472     
+ Misses      23854    23396     -458     

Files with missing lines	Coverage Δ
.../daft-distributed/src/python/ray/worker_manager.rs	0.00% <ø> (ø)
src/daft-distributed/src/pipeline_node/collect.rs	0.00% <0.00%> (ø)
src/daft-distributed/src/pipeline_node/limit.rs	0.00% <0.00%> (ø)
...rc/daft-distributed/src/pipeline_node/translate.rs	0.00% <0.00%> (ø)
src/daft-distributed/src/python/mod.rs	8.97% <0.00%> (ø)
src/daft-distributed/src/scheduling/dispatcher.rs	0.00% <0.00%> (ø)
src/daft-distributed/src/pipeline_node/mod.rs	0.00% <0.00%> (ø)
src/daft-distributed/src/plan/mod.rs	0.00% <0.00%> (ø)
src/daft-distributed/src/stage/mod.rs	0.00% <0.00%> (ø)
src/daft-distributed/src/stage/stage_builder.rs	0.00% <0.00%> (ø)

... and 40 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[samster25]

🚀