feat: LinkedIn profile search engine (Django + React + Elasticsearch + ELK)

Full-stack implementation of the Cyberyan full-stack trial task.

Backend (Django 5 / DRF)
- Normalised PostgreSQL model (Profile, Company, School, Skill, Experience,
  Education) as the source of truth, with GIN + trigram indexes.
- Self-healing CSV reader: the supplied export carries an injected watermark
  column, missing columns, rows split by broken quoting and a duplicated
  header. A signature-scored Needleman-Wunsch alignment reconstructs 284 clean
  records out of 336 physical rows; only 10 rows parse correctly without it.
- Pluggable search layer (Strategy): Elasticsearch by default, PostgreSQL
  full-text search as a fallback selected by a single environment variable.
- Keyword search with per-field boosts, fuzziness and phrase boosting, six
  faceted filters (OR within a filter, AND across filters), an experience
  range, four sort orders, highlighting and facet aggregations.
- JWT auth with rotation + blacklist, three roles, PII masking, scoped rate
  limits, a single error envelope, OpenAPI schema and health probes.

Frontend (React 18 / TypeScript / Vite)
- Debounced search with type-ahead, faceted filter panel, result cards,
  profile drawer, URL-synced search state, automatic token refresh.
- Highlight snippets rendered without dangerouslySetInnerHTML.

Infrastructure
- Hardened multi-stage images (non-root, read-only rootfs, healthchecks).
- docker-compose for the full stack plus dev and production overlays.
- ELK: structured JSON logs shipped asynchronously to Logstash, routed per
  event type, with a composable index template and a Kibana setup script.

Quality
- 61 backend tests (85% coverage), ruff/black/bandit/mypy, ESLint + tsc,
  GitHub Actions running lint, tests and both image builds.
- Persian documentation: README plus architecture, search, API, data,
  security and operations guides.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GnFo6fNaHCTAkJbfcdkqtG

backend/requirements/base.txt

@@ -0,0 +1,40 @@
+# ---------------------------------------------------------------------------
+# Runtime dependencies.
+# Pinned with compatible-release specifiers so patch level security fixes are
+# picked up while the API surface stays stable.
+# ---------------------------------------------------------------------------
+
+# Core framework
+Django~=5.1.0
+djangorestframework~=3.15.2
+django-filter~=24.3
+
+# Configuration & environment
+django-environ~=0.11.2
+
+# Database
+psycopg[binary]~=3.2.3
+
+# Authentication / authorisation
+djangorestframework-simplejwt~=5.3.1
+argon2-cffi~=23.1.0
+
+# API schema & interactive documentation
+drf-spectacular~=0.27.2
+
+# Cross origin access for the SPA
+django-cors-headers~=4.4.0
+
+# Cache / throttle backend
+redis~=5.1.1
+django-redis~=5.4.0
+
+# Search engine client
+elasticsearch~=8.15.1
+
+# Observability: ship structured logs to Logstash without blocking requests
+python-logstash-async~=4.0
+
+# Serving
+gunicorn~=23.0.0
+whitenoise~=6.7.0

backend/requirements/dev.txt

@@ -0,0 +1,20 @@
+-r base.txt
+
+# Testing
+pytest~=8.3.3
+pytest-django~=4.9.0
+pytest-cov~=5.0.0
+factory-boy~=3.3.1
+
+# Quality gates
+ruff~=0.6.9
+black~=24.10.0
+mypy~=1.11.2
+django-stubs[compatible-mypy]~=5.1.0
+djangorestframework-stubs~=3.15.1
+bandit~=1.7.10
+pip-audit~=2.7.3
+
+# Developer experience
+django-extensions~=3.2.3
+ipython~=8.28.0