Add repository infrastructure: Dependabot, issue/PR templates, CODEOWNERS, and configuration fixes

[Copilot]

Adds missing GitHub repository infrastructure to improve dependency management, contributor experience, and project configuration.

Changes

• Dependabot (.github/dependabot.yml): Updated labels to automated, standardized PR limit to 5 for both pip and github-actions

• Issue Templates (.github/ISSUE_TEMPLATE/): Added bug_report.md, feature_request.md, and config.yml linking to Discussions and documentation

• PR Template (.github/PULL_REQUEST_TEMPLATE.md): Added standardized template with type classification and checklist

• CODEOWNERS (.github/CODEOWNERS): Added /src/eigenscript/compiler/ section, expanded CI/CD coverage from /.github/workflows/ to /.github/

• Documentation URL (pyproject.toml): Fixed from GitHub repo path to actual docs site: https://inauguralphysicist.github.io/EigenScript/

• Script Organization: Moved demo_phase_3_2.sh to scripts/ directory, updated path navigation from cd "$(dirname "$0")" to cd "$(dirname "$0")/.."

• Coverage Badge (README.md): Added Codecov badge after existing status badges

Original prompt

Summary

This PR addresses several areas for improvement identified in the repository to enhance CI/CD, contributor experience, and project configuration.

Changes to Make

1. Add Dependabot Configuration

Create .github/dependabot.yml to enable automated dependency updates:

version: 2
updates:
  - package-ecosystem: "pip"
    directory: "/"
    schedule:
      interval: "weekly"
    open-pull-requests-limit: 5
    labels:
      - "dependencies"
      - "automated"

  - package-ecosystem: "github-actions"
    directory: "/"
    schedule:
      interval: "weekly"
    open-pull-requests-limit: 5
    labels:
      - "dependencies"
      - "automated"

2. Add Issue Templates

Create .github/ISSUE_TEMPLATE/bug_report.md:

---
name: Bug Report
about: Report a bug to help us improve EigenScript
title: '[BUG] '
labels: bug
assignees: ''
---

## Bug Description
A clear and concise description of what the bug is.

## To Reproduce
Steps to reproduce the behavior:
1. Run '...'
2. With input '...'
3. See error

## Expected Behavior
A clear description of what you expected to happen.

## Actual Behavior
What actually happened.

## Environment
- OS: [e.g., Ubuntu 22.04, macOS 14, Windows 11]
- Python version: [e.g., 3.11]
- EigenScript version: [e.g., 0.4.1]

## Code Sample
```eigenscript
# Minimal code to reproduce the issue

Additional Context

Add any other context about the problem here.

Create `.github/ISSUE_TEMPLATE/feature_request.md`:
```markdown
---
name: Feature Request
about: Suggest a new feature for EigenScript
title: '[FEATURE] '
labels: enhancement
assignees: ''
---

## Feature Description
A clear and concise description of the feature you'd like.

## Use Case
Describe the problem this feature would solve or the use case it enables.

## Proposed Syntax/API
If applicable, show how this feature might look in EigenScript:
```eigenscript
# Example of proposed syntax

Alternatives Considered

Describe any alternative solutions or features you've considered.

Additional Context

Add any other context, references, or screenshots about the feature request.

Create `.github/ISSUE_TEMPLATE/config.yml`:
```yaml
blank_issues_enabled: true
contact_links:
  - name: GitHub Discussions
    url: https://github.com/InauguralSystems/EigenScript/discussions
    about: Ask questions and discuss ideas with the community
  - name: Documentation
    url: https://inauguralphysicist.github.io/EigenScript/
    about: Check the documentation for answers

3. Add Pull Request Template

Create .github/PULL_REQUEST_TEMPLATE.md:

## Description
Brief description of the changes in this PR.

## Related Issue
Fixes #(issue number) or Related to #(issue number)

## Type of Change
- [ ] Bug fix (non-breaking change that fixes an issue)
- [ ] New feature (non-breaking change that adds functionality)
- [ ] Breaking change (fix or feature that would cause existing functionality to change)
- [ ] Documentation update
- [ ] Performance improvement
- [ ] Code refactoring (no functional changes)

## Checklist
- [ ] My code follows the project's code style (ran `black` and `flake8`)
- [ ] I have added tests that prove my fix/feature works
- [ ] All new and existing tests pass (`pytest tests/`)
- [ ] I have updated the documentation if needed
- [ ] I have updated the CHANGELOG.md if this is a notable change

## Testing
Describe how you tested these changes.

## Screenshots (if applicable)
Add screenshots to help explain your changes.

4. Add CODEOWNERS

Create .github/CODEOWNERS:

# Default owners for everything in the repo
* @InauguralPhysicist

# Compiler-specific code
/src/eigenscript/compiler/ @InauguralPhysicist

# Documentation
/docs/ @InauguralPhysicist
*.md @InauguralPhysicist

# CI/CD configuration
/.github/ @InauguralPhysicist

5. Fix Documentation URL in pyproject.toml

Update line 49 in pyproject.toml from:

Documentation = "https://github.com/InauguralSystems/EigenScript/docs"

to:

Documentation = "https://inauguralphysicist.github.io/EigenScript/"

6. Move demo script to scripts directory

Move demo_phase_3_2.sh from the repository root to scripts/demo_phase_3_2.sh.

7. Add coverage badge to README.md

Add a coverage badge after line 13 in README.md (after the existing badges):

![Coverage](https://codecov.io/gh/InauguralSystems/EigenScript/branch/main/graph/badge.svg)

Why These Changes Matter

• Dependabot: Automatically keeps dependencies secure and up-to-date
• Issue Templates: Guides contributors to provide necessary information, reducing back-and-forth
• PR Template: Ensures consistent quality and documentation of changes
• CODEOWNERS: Automates review assignment as the project grows
• Documentation URL fix: Directs users to the correct documentation site
• Script organization: Cleaner repository structure
• Coverage badge: Transparency about test coverage

This pull request was created from Copilot chat.

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