feat: Add pull request template to standardize PR submissions

.github/pull_request_template.md

@@ -0,0 +1,76 @@
+## Summary
+
+<!-- What does this PR do? Why is this change needed? Be specific. -->
+
+## Type of change
+
+- [ ] New feature (`Added`)
+- [ ] Change to existing behavior (`Changed`)
+- [ ] Bug fix (`Fixed`)
+- [ ] Security / infrastructure (`Security`)
+- [ ] Internal refactor (no behavioral change)
+- [ ] Docs / changelog only
+
+---
+
+## PR Checklist
+
+> All applicable items must be checked before requesting review.
+> Reviewers are authorized to close and request resubmission of PRs that do not meet these standards.
+
+### Code & Environment
+- [ ] Tested locally against the **authorized Devaron Cluster** (no external or unauthorized infrastructure used)
+- [ ] No personal IDE/environment files committed (`.vscode`, `.devcontainer`, etc.)
+- [ ] No `root` user configurations introduced
+- [ ] `Dockerfile` and `.dockerignore` comply with build context standards (`/app` only, no `/workspace`)
+
+### Ingestion Files
+- [ ] **No ingestion files were added or modified in this PR**
+- [ ] **Ingestion files were added or modified** and are committed to the repository under `ingestion/` or `data/`
+
+### Environment Variables
+- [ ] **No new environment variables were introduced in this PR**
+- [ ] **New variables were introduced** and are fully documented in the `.env` table in `README.md`
+
+If new variables were added, list them here:
+
+| Variable | Required | Description | Example value |
+|---|---|---|---|
+| `VARIABLE_NAME` | Yes / No | What it does | `example` |
+
+### Changelog
+- [ ] **Not required** — internal refactor, typo/comment fix, or zero behavioral impact
+- [ ] **Updated** — entry added to `changelog` with correct version bump and today's date
+
+### Documentation
+- [ ] **Not required** — internal change with no impact on setup, API, or usage
+- [ ] **Updated** — `README.md` or relevant docs reflect this change
+
+---
+
+## Changelog entry
+
+<!-- Paste the entry you added, or write "N/A" -->
+
+```
+## [X.Y.Z] - YYYY-MM-DD
+
+### Added / Changed / Fixed / Security
+- LABEL: Description.
+```
+
+---
+
+## Infrastructure status during testing
+
+| Tunnel | Status |
+|---|---|
+| Ollama (port 11434) | `active` / `N/A` |
+| Elasticsearch (port 9200) | `active` / `N/A` |
+| PostgreSQL (port 5432) | `active` / `N/A` |
+
+---
+
+## Notes for reviewer
+
+<!-- Anything the reviewer should pay special attention to. If none, write "None." -->