Arena/01a0e9a2 developer ecosystem (#216)

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## Summary

<!-- What does this PR do, and why? -->

Closes #

## Type of change

- [ ] 🐛 Bug fix (non-breaking change that fixes an issue)
- [ ] ✨ New feature (non-breaking change that adds functionality)
- [ ] 💥 Breaking change (would change existing behaviour)
- [ ] 🕳️ Soundness fix (fixes a checker/proof false-negative)
- [ ] 📖 Documentation
- [ ] 🧹 Refactor / tech debt (behaviour-preserving)
- [ ] ⚡ Performance
- [ ] 🔧 Build / CI / tooling

## How has this been verified?

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report?
     Don't cite a status doc — cite the command and its output. -->

## Checklist

- [ ] My commits are **signed** (`git commit -S`).
- [ ] I ran the project's own checks/tests locally and they pass.
- [ ] New files carry the correct `SPDX-License-Identifier` (code/config
`MPL-2.0`,
      prose `CC-BY-SA-4.0`); I did not relicense existing files.
- [ ] Docs are updated, and no public claim now overstates what the code
does.
- [ ] I have not introduced a soundness hole (or I have flagged where I
might have).

## Notes for reviewers

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---------

Co-authored-by: arena-agent <297053741+arena-agent@users.noreply.github.com>

Author: hyperpolymath

.gitleaks.toml

@@ -41,10 +41,6 @@ paths = [
   # named secret_value.toml — inputs to a manifest/invariant test.
   '''(^|/)shellstate/test/''',
 
-  # Documentation. The match is an illustrative connection string in a
-  # distributed-filesystem explainer.
-  '''(^|/)czech-file-knife/docs/''',
-
   # A DETECTOR definition: the flagged line is the literal '-----BEGIN
   # PRIVATE KEY-----' inside a list of patterns this contract searches FOR.
   # The scanner matched the rule, not a key.

.hypatia-baseline.json

@@ -55,14 +55,6 @@
     "note": "Translation target fixture: Python source used to demonstrate julianiser Python-to-Julia translation patterns. This file exists to be translated AWAY from Python, not as functional Python code.",
     "tracking_issue": "hyperpolymath/developer-ecosystem#111"
   },
-  {
-    "severity": "high",
-    "rule_module": "cicd_rules",
-    "type": "banned_language_file",
-    "file_pattern": "czech-file-knife/cfk-ios/**",
-    "note": "cfk-ios is the iOS File Provider Extension for czech-file-knife; requires Swift for NSFileProviderReplicatedExtension (no Tauri/Dioxus equivalent for this specific iOS API).",
-    "tracking_issue": "hyperpolymath/developer-ecosystem#111"
-  },
   {
     "severity": "high",
     "rule_module": "cicd_rules",

CHANGELOG.adoc

@@ -16,6 +16,14 @@ https://semver.org/spec/v2.0.0.html[Semantic Versioning].
 
 === [Unreleased]
 
+==== Removed
+
+* `czech-file-knife/` extracted to its own repository,
+  https://github.com/hyperpolymath/czech-file-knife[hyperpolymath/czech-file-knife]
+  (it was only held here). The standalone, RSR-template-compliant tree is the
+  `czech-file-knife/` prefix at commit `60ba3be3`; history is preserved
+  with `git subtree split --prefix=czech-file-knife`.
+
 ==== Fixed
 
 * fix(licence): developer-ecosystem — clear scaffold-placeholder leak