ci(github): overhaul CI/CD workflows for PR and issue management (#734)

[vansh-09]

Summary [required]

This change replaces several legacy workflows with a suite of specialized
actions to improve repository maintenance and contributor experience:

• Implement automated issue triage and classification based on content.
• Add PR difficulty detection (beginner to critical) based on file/line changes.
• Add PR quality scoring (clean/exceptional) using heuristic analysis.
• Implement PR type labeling (bug, feature, docs, etc.) via title and branch analysis.
• Automate PR assignment to authors and add GSSoC approval labels.
• Enable label inheritance from linked issues to PRs.
• Add automated reviewer assignment for new pull requests.
• Implement a stale assignee cleanup job to maintain active issue participation.
• Add an auto-assignment mechanism for contributors claiming issues via comments.

Related Issue [required]

Closes #734

Type of Change [required]

• Bug fix — resolves a broken behaviour
• Feature — adds new functionality
• Data — adds new projects to data/projects.json
• Documentation — updates docs, README, or code comments only
• Style — CSS or visual changes only, no logic change
• Refactor — restructures code without changing behaviour
• Test — adds or updates tests

What Was Changed [required]

Added:

• github/workflows/difficulty.yml
• github/workflows/issue-triage.yml
• github/workflows/pr-auto-assign.yml
• github/workflows/pr-label-inheritance.yml
• github/workflows/pr-reviewer.yml
• github/workflows/quality-labeller.yml
• github/workflows/stale-assignees.yml
• github/workflows/type-labeller.yml

Deleted:

• github/workflows/auto-file-labels.yml
• github/workflows/auto-label-issues.yml
• github/workflows/auto-label-prs.yml

How to Test This PR [required]

N/A

Test Results [required]

N/A

Self-Review Checklist [required]

• I have read CONTRIBUTING.md and followed all guidelines
• My branch name follows the convention: feat/, fix/, docs/, data/, style/, test/
• I have run python tests/test_basic.py and all 27 tests pass
• I have run flake8 . locally and there are no errors
• I have not introduced any print() or console.log() debug statements
• Every new function I wrote has a docstring
• I have not modified files outside the scope of the linked issue
• If I changed the UI, I tested it at 375px (mobile) and 1280px (desktop)
• If I added a project to the dataset, it has all required JSON fields

[vercel]

@vansh-09 is attempting to deploy a commit to the komalsony234-1530's projects Team on Vercel.

A member of the Team first needs to authorize it.

[vansh-09]

@komalharshita please review

[komalharshita]

Thank you for the contribution and the significant effort put into improving repository automation.

After reviewing the changes, I’m not comfortable merging this PR in its current form. While the workflows are well structured, this PR introduces a very large-scale overhaul of the repository’s CI/CD and project management automation, including issue assignment, PR assignment, reviewer requests, label inheritance, difficulty classification, quality scoring, stale issue handling, and multiple new labeling systems.

These changes significantly alter repository governance and maintenance workflows, and would require broader discussion and consensus before adoption. The scope is also quite large for a single PR, making it difficult to evaluate and maintain safely.

For now, I’m going to close this PR. If there are specific workflow improvements you’d like to propose, please consider opening smaller, focused PRs that address one automation area at a time so they can be reviewed independently.

Thank you again for the contribution and effort.