docs: adopt shared contribution policy in Backtest

.github/ISSUE_TEMPLATE/bug.yml

@@ -1,5 +1,5 @@
 name: Bug report
-description: Report reproducible incorrect behavior in ecosystem policy or tooling
+description: Report one reproducible Backtest defect
 title: "[Bug]: "
 labels:
   - "type: bug"
@@ -10,7 +10,9 @@ body:
   - type: markdown
     attributes:
       value: |
-        Search existing issues first. Do not disclose suspected vulnerabilities here.
+        Search existing issues first and report one problem here.
+        Read [CONTRIBUTING.md](https://github.com/ml4t/backtest/blob/main/CONTRIBUTING.md).
+        Report suspected vulnerabilities through the private security link instead.
   - type: dropdown
     id: library
     attributes:
@@ -50,13 +52,16 @@ body:
     id: expected
     attributes:
       label: Expected behavior
+      description: >-
+        For a numerical defect, state the intended definition and expected result. An earlier
+        output alone does not establish correctness.
     validations:
       required: true
   - type: textarea
     id: reproduction
     attributes:
       label: Minimal reproduction
-      description: Provide the smallest complete example and error output.
+      description: Provide the smallest complete public API or user workflow example and error output.
     validations:
       required: true
   - type: dropdown
@@ -78,3 +83,12 @@ body:
       description: State the observable conditions that demonstrate the issue is resolved.
     validations:
       required: true
+  - type: textarea
+    id: ai_assistance
+    attributes:
+      label: AI assistance
+      description: >-
+        State whether AI tools helped prepare this report and which parts they produced.
+        Write "None" if none.
+    validations:
+      required: true

.github/ISSUE_TEMPLATE/config.yml

@@ -3,6 +3,6 @@ contact_links:
   - name: Security vulnerability
     url: https://github.com/ml4t/backtest/security/advisories/new
     about: Report suspected vulnerabilities privately.
-  - name: Usage questions
-    url: https://github.com/orgs/ml4t/discussions
-    about: Ask questions that do not describe a defect or requested change.
+  - name: Usage documentation
+    url: https://www.ml4trading.io/docs/backtest/user-guide/
+    about: Read the Backtest user guide for usage instructions and examples.

.github/ISSUE_TEMPLATE/documentation.yml

@@ -7,6 +7,11 @@ labels:
   - "status: needs-triage"
   - "compatibility: none"
 body:
+  - type: markdown
+    attributes:
+      value: |
+        Search existing issues and report one documentation problem.
+        Read [CONTRIBUTING.md](https://github.com/ml4t/backtest/blob/main/CONTRIBUTING.md).
   - type: dropdown
     id: library
     attributes:
@@ -53,3 +58,12 @@ body:
       label: Acceptance criteria
     validations:
       required: true
+  - type: textarea
+    id: ai_assistance
+    attributes:
+      label: AI assistance
+      description: >-
+        State whether AI tools helped prepare this report and which parts they produced.
+        Write "None" if none.
+    validations:
+      required: true

.github/ISSUE_TEMPLATE/feature.yml

@@ -7,6 +7,11 @@ labels:
   - "status: needs-triage"
   - "compatibility: affected"
 body:
+  - type: markdown
+    attributes:
+      value: |
+        Search existing issues and describe one change.
+        Read [CONTRIBUTING.md](https://github.com/ml4t/backtest/blob/main/CONTRIBUTING.md).
   - type: dropdown
     id: library
     attributes:
@@ -64,3 +69,12 @@ body:
       label: Acceptance criteria
     validations:
       required: true
+  - type: textarea
+    id: ai_assistance
+    attributes:
+      label: AI assistance
+      description: >-
+        State whether AI tools helped prepare this request and which parts they produced.
+        Write "None" if none.
+    validations:
+      required: true

.github/PULL_REQUEST_TEMPLATE.md

@@ -2,25 +2,48 @@
 
 Closes #
 
+Keep this PR focused on one issue. Automated dependency updates and administrative metadata
+changes may state that exception here instead of linking an issue.
+
 ## Outcome
 
 Describe the user-visible or standards outcome.
 
+## Bug regression evidence
+
+For a bug fix, exercise the affected public API or user workflow on both revisions. The test must
+fail because of the defect on the base and pass with the fix. State "Not a bug fix" when this
+section does not apply.
+
+- Base revision, command, and observed failure:
+- Fix revision, command, and passing result:
+
 ## Compatibility
 
 - [ ] No public compatibility impact
 - [ ] Compatibility impact is documented in the owning issue and migration guidance
 
+For numerical changes, state the intended result and how it was checked independently of the old
+output. If the definition, annualization, sign convention, or default changes, cite the decision in
+the owning issue and describe the compatibility impact.
+
 ## Verification
 
-- [ ] Tests reproduce the prior failure or verify the requested behavior
+- [ ] Bug regression fails on the base and passes with the fix, or this is not a bug fix
 - [ ] Ruff lint and format checks pass
 - [ ] `ty` passes
 - [ ] Test suite passes
 - [ ] Package build passes when applicable
 - [ ] Strict MkDocs build passes when documentation is affected
 - [ ] Ecosystem qualification passes
 
+List the commands actually run and their results. Explain any unchecked item.
+
+## AI assistance
+
+State whether AI tools helped produce the code, tests, documentation, or PR text, and identify the
+parts they produced. Write "None" if none. Confirm that you reviewed and tested any AI-assisted work.
+
 ## Documentation and release
 
 State the documentation, release notes, and patch-release work required after merge.

CONTRIBUTING.md

@@ -0,0 +1,26 @@
+# Contributing to ml4t-backtest
+
+Read the [ML4T contribution policy](https://github.com/ml4t/ecosystem/blob/main/CONTRIBUTING.md)
+before opening an issue or pull request. This guide identifies the Backtest-specific entry points.
+
+Search [existing issues](https://github.com/ml4t/backtest/issues) first. Report one problem per
+issue. For a bug, include the affected package version, Python and operating-system versions,
+expected and observed behavior, and a complete example that reproduces the result. Report suspected
+vulnerabilities through the [private security process](SECURITY.md).
+
+Keep each pull request focused on one issue and include a closing reference such as `Closes #123`.
+Automated dependency updates and administrative metadata changes do not need a separate issue. For
+a bug fix, run a regression through the affected public API or user workflow against both the base
+revision and the fix. Record both revisions, commands, and results in the pull request. The test
+must fail because of the defect on the base and pass with the fix. Documentation changes need
+documentation checks, not an artificial regression test.
+
+For numerical defects, establish the intended result independently of the old output. If the
+definition, annualization, sign convention, or default changes, agree on the expected behavior in
+the owning issue and describe the compatibility impact.
+
+Run the relevant commands in the [Development section](README.md#development) and the
+[repository quality commands](AGENTS.md#quality-commands), then report the results. CI also checks
+compatibility, security, parity, and package artifacts. State whether AI tools helped with the issue
+or pull request and which parts they produced. Review and test that work yourself; be prepared to
+explain it during review.

README.md

@@ -476,6 +476,8 @@ Release-critical validation files are listed in
 [`validation/release_checks.txt`](validation/release_checks.txt). CI runs the supported gate set,
 including compatibility, security, parity, and artifact qualification.
 
+Read [CONTRIBUTING.md](CONTRIBUTING.md) before filing an issue or pull request.
+
 ## Known Limitations
 
 See [LIMITATIONS.md](LIMITATIONS.md) for documented assumptions: