chore: add Issue and PR templates

.github/workflows/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,121 @@
+name: "🐛 Bug Report"
+description: "Report a bug or unexpected behavior in cqlib"
+title: "[BUG] "
+labels: ["bug", "triage"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        **Thank you for reporting a bug!**
+
+        Before submitting:
+        - Search [existing issues](https://github.com/cq-lib/cqlib/issues) to avoid duplicates
+        - Security vulnerabilities → email <tianyan@chinatelecom.cn> (see [SECURITY.md](SECURITY.md))
+
+  - type: input
+    id: version
+    attributes:
+      label: "cqlib version"
+      description: "Run `pip show cqlib` or check `cargo.toml`"
+      placeholder: "e.g. 0.1.0, commit a1b2c3d"
+    validations:
+      required: true
+
+  - type: dropdown
+    id: component
+    attributes:
+      label: "Which component?"
+      options:
+        - "cqlib-core (Rust core)"
+        - "binding-python (Python bindings)"
+        - "binding-c (C bindings)"
+        - "cqlib (public Rust crate)"
+        - "Other / Not sure"
+    validations:
+      required: true
+
+  - type: textarea
+    id: environment
+    attributes:
+      label: "Environment"
+      description: "OS, architecture, Rust version, Python version"
+      placeholder: |
+        - OS: Ubuntu 22.04 / macOS 14 / Windows 11
+        - Architecture: x86_64 / ARM64
+        - Rust: 1.85.0
+        - Python: 3.12.0
+      render: markdown
+    validations:
+      required: true
+
+  - type: textarea
+    id: steps
+    attributes:
+      label: "Steps to reproduce"
+      description: "Minimal code to reproduce the bug"
+      placeholder: |
+        **Python:**
+        ```python
+        from cqlib import Circuit
+        qc = Circuit(2)
+        qc.h(0)
+        qc.cx(0, 1)
+        # bug happens here
+        ```
+
+        **Rust:**
+        ```rust
+        use cqlib_core::circuit::{Circuit, Qubit};
+        let mut qc = Circuit::new(2);
+        // bug happens here
+        ```
+
+        **C:**
+        ```c
+        #include <cqlib/circuit.h>
+        cqlib_circuit_t *qc = cqlib_circuit_new(2);
+        // bug happens here
+        ```
+      render: markdown
+    validations:
+      required: true
+
+  - type: textarea
+    id: expected
+    attributes:
+      label: "Expected behavior"
+      placeholder: "What did you expect to happen?"
+    validations:
+      required: true
+
+  - type: textarea
+    id: actual
+    attributes:
+      label: "Actual behavior"
+      placeholder: "What actually happened? Include full error messages, logs, or stack traces."
+      render: text
+    validations:
+      required: true
+
+  - type: textarea
+    id: quantum_context
+    attributes:
+      label: "Quantum-specific context (if applicable)"
+      description: "For issues related to simulation, noise, or numerical computation"
+      placeholder: |
+        - Input circuit / gates
+        - Parameters used (theta, random seed, etc.)
+        - Simulator / backend configuration
+        - Noise model parameters
+        - Expected vs actual tolerance / precision
+      render: markdown
+    validations:
+      required: false
+
+  - type: textarea
+    id: additional
+    attributes:
+      label: "Additional context"
+      placeholder: "Screenshots, related issues, workarounds tried, etc."
+    validations:
+      required: false

.github/workflows/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,11 @@
+blank_issues_enabled: false
+contact_links:
+  - name: "\uD83D\uDCAC Ask a question in Discussions"
+    url: https://github.com/cq-lib/cqlib/discussions
+    about: "Please use Discussions for general questions and community conversation"
+  - name: "\uD83D\uDCD6 Read the documentation"
+    url: https://qc.zdxlz.com/
+    about: "Check the official cqlib documentation before opening an issue"
+  - name: "\u270D\uFE0F Contribution guide (\u4E2D\u6587)"
+    url: https://github.com/cq-lib/cqlib/blob/main/CONTRIBUTING.CN.md
+    about: "Read the contributing guide before submitting code"

.github/workflows/ISSUE_TEMPLATE/feature_request.yml

@@ -0,0 +1,85 @@
+name: "\U0001F680 Feature Request"
+description: "Suggest a new feature or enhancement for cqlib"
+title: "[FEATURE] "
+labels: ["enhancement", "triage"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        **Thank you for suggesting a feature!**
+
+        Before submitting:
+        - Search [existing issues](https://github.com/cq-lib/cqlib/issues) to check if this has already been proposed
+        - Major API changes should be discussed in an Issue first (see [CONTRIBUTING.md](CONTRIBUTING.md))
+
+  - type: textarea
+    id: problem
+    attributes:
+      label: "Problem statement"
+      description: "What problem does this feature solve? Describe your use case."
+      placeholder: "E.g., I want to run VQE on custom Hamiltonians but the current API requires..."
+    validations:
+      required: true
+
+  - type: dropdown
+    id: area
+    attributes:
+      label: "Which area does this affect?"
+      multiple: true
+      options:
+        - "Circuit Construction"
+        - "Intermediate Representation (IR / Optimization)"
+        - "Compiler Passes (gate decomposition / routing / scheduling)"
+        - "Device Model (calibration / topology / noise)"
+        - "Simulation (state vector / noise model)"
+        - "Error Mitigation (ZNE / Virtual Distillation)"
+        - "Visualization"
+        - "Python Bindings"
+        - "C Bindings"
+        - "Documentation / Examples"
+    validations:
+      required: true
+
+  - type: textarea
+    id: proposal
+    attributes:
+      label: "Proposed solution"
+      description: "Describe what you would like to see. Code snippets or pseudo-code are welcome."
+      placeholder: |
+        ```python
+        # Example of how the API might look
+        from cqlib import Circuit, VQE
+
+        qc = Circuit(4)
+        ...
+        result = VQE(qc, hamiltonian).run()
+        ```
+      render: markdown
+    validations:
+      required: true
+
+  - type: textarea
+    id: alternatives
+    attributes:
+      label: "Alternatives considered"
+      description: "What workarounds have you tried? Are there existing libraries that solve this?"
+    validations:
+      required: false
+
+  - type: checkboxes
+    id: scope
+    attributes:
+      label: "Scope check"
+      options:
+        - label: "This is within cqlib's scope (quantum computing SDK: circuits, IR, compilation, simulation, error mitigation)"
+          required: false
+        - label: "I am willing to contribute a PR for this feature"
+          required: false
+
+  - type: textarea
+    id: additional
+    attributes:
+      label: "Additional context"
+      placeholder: "References, papers, similar features in other frameworks (Qiskit, Cirq, PennyLane, etc.)"
+    validations:
+      required: false

.github/workflows/ISSUE_TEMPLATE/question.yml

@@ -0,0 +1,60 @@
+name: "\u2753 Question"
+description: "Ask a question about using cqlib"
+title: "[QUESTION] "
+labels: ["question", "triage"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        **Welcome!** This template is for usage questions, troubleshooting help, and general inquiries.
+
+        Before asking:
+        - Check the [README](README.md) and [documentation](https://qc.zdxlz.com/)
+        - Search [existing questions](https://github.com/cq-lib/cqlib/issues?q=label%3Aquestion)
+
+  - type: dropdown
+    id: topic
+    attributes:
+      label: "What is your question about?"
+      options:
+        - "Installation / Build"
+        - "API Usage"
+        - "Quantum Computing Theory"
+        - "Performance / Optimization"
+        - "Documentation"
+        - "Other"
+    validations:
+      required: true
+
+  - type: textarea
+    id: question
+    attributes:
+      label: "Your question"
+      description: "Describe what you are trying to do and what you need help with."
+      placeholder: |
+        I am trying to...
+        I have read / tried...
+        I expected..., but got...
+    validations:
+      required: true
+
+  - type: textarea
+    id: code
+    attributes:
+      label: "Relevant code (if applicable)"
+      description: "Paste the code or circuit you are working with."
+      render: markdown
+    validations:
+      required: false
+
+  - type: textarea
+    id: context
+    attributes:
+      label: "Environment"
+      description: "If relevant: cqlib version, OS, Python/Rust version"
+      placeholder: |
+        - cqlib version: 0.1.0
+        - Python: 3.12.0
+        - OS: Ubuntu 22.04
+    validations:
+      required: false

.github/workflows/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,21 @@
+<!--
+Before submitting:
+- Read the [Contributing Guide](CONTRIBUTING.md)
+- Run tests: `cargo test --all` and `pytest tests/python/`
+- Run lints: `cargo fmt --check`, `cargo clippy`, `ruff check`
+-->
+
+## Description
+
+<!-- Briefly describe what this PR does and why. -->
+
+## Related Issues
+
+<!-- Closes #123 | Related to #456 -->
+
+## Checklist
+
+- [ ] I have read the [Contributing Guide](CONTRIBUTING.md)
+- [ ] Lints and tests pass locally
+- [ ] I have added tests that prove my fix/feature works
+- [ ] I have updated documentation as needed