refactor: move stacks-node crate to workspace root

[fdefelici]

Description

This patch moves the stacks-node crate from testnet/stacks-node to the root of the workspace, aligning it with the structure of other crates.

Additionally, this PR includes a small cleanup of the .gitignore file, other than the one required for testnet/ refactor.

NOTE: stacks-networks/actions need to be updated (about nextest cache preparation). Here the related patch PR #78 with a "fallback compatibility mode" that has been merged

Applicable issues

• fixes Refactor: move stacks-node crate to workspace root #6252

Additional info (benefits, drawbacks, caveats)

After the move, references to the testnet/ path remain in the following locations:

• CONTRIBUTING.md
• migration-verification tool

> CONTRIBUTING.md
In the coding guidelines section, the following example links still reference the previous path:

https://github.com/stacks-network/stacks-core/blob/4852d6439b473e24705f14b8af637aded33cb422/testnet/stacks-node/src/neon_node.rs#L17

https://github.com/stacks-network/stacks-core/blob/4852d6439b473e24705f14b8af637aded33cb422/testnet/stacks-node/src/neon_node.rs#L1148-L1216

Proposal: Leave these links as-is for now, since they serve as point-in-time examples, OR we can update them in a follow-up PR after this one is merged, once we have a new commit to reference

> MIGRATION VERIFICATION TOOL
This tool was used during the transition from Stacks 1.0 to Stacks 2.0

Proposal: If the tool is no longer needed, we should consider removing it.

UPDATE: As shared during the nakasync we opted for:

• keeping current CONTRIBUTING.md by now.
• removing the MIGRATION VERIFICATION tool in a dedicated PR (opened issue: chore: remove migration-verification tool #6264)

Checklist

• Test coverage for new or modified code paths
• Changelog is updated
• Required documentation changes (e.g., docs/rpc/openapi.yaml and rpc-endpoints.md for v2 endpoints, event-dispatcher.md for new events)
• New clarity functions have corresponding PR in clarity-benchmarking repo
• New integration test(s) added to bitcoin-tests.yml

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.65%. Comparing base (ddcff25) to head (d85ae0f).
Report is 5 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #6254      +/-   ##
===========================================
- Coverage    81.95%   80.65%   -1.30%     
===========================================
  Files          546      546              
  Lines       347235   347235              
  Branches       323      323              
===========================================
- Hits        284576   280065    -4511     
- Misses       62651    67162    +4511     
  Partials         8        8              

Files with missing lines	Coverage Δ
...-node/src/burnchains/bitcoin_regtest_controller.rs	76.88% <ø> (ø)
stacks-node/src/burnchains/mocknet_controller.rs	69.12% <ø> (ø)
stacks-node/src/burnchains/mod.rs	62.50% <ø> (ø)
stacks-node/src/event_dispatcher.rs	87.68% <ø> (ø)
stacks-node/src/globals.rs	72.29% <ø> (ø)
stacks-node/src/keychain.rs	81.23% <ø> (ø)
stacks-node/src/main.rs	0.00% <ø> (ø)
stacks-node/src/monitoring/mod.rs	100.00% <ø> (ø)
stacks-node/src/monitoring/prometheus.rs	80.43% <ø> (ø)
stacks-node/src/nakamoto_node.rs	90.81% <ø> (ø)
... and 44 more

... and 47 files with indirect coverage changes

---

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[Jiloc]

good job! I believe we are almost there, I also grepped for all testnet in the code, I believe you missed only

• stacks-core/contrib/tools/local-mutation-testing.sh

  Line 38 in a5587d1

  "testnet")

• https://github.com/stacks-network/stacks-core/blob/a5587d13c51829f49a7645d9484469e5ca891e29/docs/mutation-testing.md a few references to the "testnet" folder

that needs to be changed to "stacks-node" now. I'll give a second look at the results

[fdefelici]

good job! I believe we are almost there, I also grepped for all testnet in the code, I believe you missed only

• stacks-core/contrib/tools/local-mutation-testing.sh

  Line 38 in a5587d1

  "testnet")

• https://github.com/stacks-network/stacks-core/blob/a5587d13c51829f49a7645d9484469e5ca891e29/docs/mutation-testing.md a few references to the "testnet" folder

that needs to be changed to "stacks-node" now. I'll give a second look at the results

Maybe the mutation testing script and related documentation can be removed in a dedicated PR.
What do you think @wileyj? Is this related to #6137 and stacks-actions issue stacks-network/actions#80 ?

[wileyj]

good job! I believe we are almost there, I also grepped for all testnet in the code, I believe you missed only

• stacks-core/contrib/tools/local-mutation-testing.sh

  Line 38 in a5587d1

  "testnet")

• https://github.com/stacks-network/stacks-core/blob/a5587d13c51829f49a7645d9484469e5ca891e29/docs/mutation-testing.md a few references to the "testnet" folder

that needs to be changed to "stacks-node" now. I'll give a second look at the results

Maybe the mutation testing script and related documentation can be removed in a dedicated PR. What do you think @wileyj? Is this related to #6137 and stacks-actions issue stacks-network/actions#80 ?

Correct - i thought i had commented on these files in another PR, but i can't find it so i'll assume it didn't happen.

I would say we can remove those files in this PR, or ack that the changes missed are OK since they will be removed later.

[fdefelici]

Maybe the mutation testing script and related documentation can be removed in a dedicated PR. What do you think @wileyj? Is this related to #6137 and stacks-actions issue stacks-network/actions#80 ?

Correct - i thought i had commented on these files in another PR, but i can't find it so i'll assume it didn't happen.

I would say we can remove those files in this PR, or ack that the changes missed are OK since they will be removed later.

Ok. I opened a specific issue for this #6275 to keep this PR scoped

[Jiloc]

lgtm!

[obycode]

LGTM!

[kantai]

🎉