feat: redesigned protocol

[lars-reimann]

Closes #22
Closes #90
Closes #92

Summary of Changes

• Use Socket.io instead of plain websockets. The rooms help send messages only to a subset of clients. Automatic reconnection saves us some effort.
• Send runtime warnings.
• Replace save_placeholder with two methods to either just report that a placeholder was computed and another to immediately send the value.
• Augment progress message to send percentage of work done and an optional message. We can later use this to report, say, how many epochs are already done when training a neural network.

Message client -> server:

• run - run a pipeline
• shutdown - shutdown the server

Messages server -> client:

• placeholder_value - send the value of a placeholder
• progress - report that a placeholder was computed
• runtime_warning - report a warning while running the pipeline
• runtime_error- report an error while running the pipeline
• done - finished running the pipeline

TODOs

• Test sending a placeholder_value message
• Test tableWindows argument of run message
• Test cwd argument of run message

[github-actions]

🦙 MegaLinter status: ❌ ERROR

Descriptor	Linter	Files	Fixed	Errors	Elapsed time
✅ PYTHON	black	29	6	0	1.07s
❌ PYTHON	mypy	29		1	0.18s
✅ PYTHON	ruff	29	6	0	0.03s
✅ REPOSITORY	git_diff	yes		no	0.02s

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[codecov]

Codecov Report

Attention: Patch coverage is 97.35849% with 7 lines in your changes are missing coverage. Please review.

Project coverage is 95.92%. Comparing base (b55f44e) to head (3862377).

❗ Current head 3862377 differs from pull request most recent head e0d0296. Consider uploading reports for the commit e0d0296 to get more accurate results

Files	Patch %	Lines
src/safeds_runner/server/_server.py	93.87%	3 Missing ⚠️
src/safeds_runner/interface/_reporters.py	80.00%	2 Missing ⚠️
src/safeds_runner/server/main.py	50.00%	1 Missing ⚠️
src/safeds_runner/server/messages/_from_server.py	98.14%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##              main     #106      +/-   ##
===========================================
- Coverage   100.00%   95.92%   -4.08%     
===========================================
  Files           15       21       +6     
  Lines          787      712      -75     
===========================================
- Hits           787      683     -104     
- Misses           0       29      +29     

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