docs: reorganize tree, restore architecture + research from archive, add Phase 0 reports

Active docs/ was stub scaffolding while the real docs sat in docs/_archive/.
Restore and correct them, and record the Phase 0 work.

- docs/architecture/current.md: verified system map (from archived SYSTEM_OVERVIEW,
  9 corrections against code).
- docs/research/competitors.md: sourced competitor analysis (from archived
  PRODUCT_RESEARCH, feature matrix corrected).
- docs/decisions/ADR-002-job-application-model.md: the Job/JobApplication split.
- docs/application-discovery-report.md, docs/implementation-roadmap.md,
  docs/phase-0-foundation-report.md, docs/career-workspace-branch-assessment.md.
- Remove 10 zero-byte placeholder files that advertised content that never existed.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/02-product-principles.md

@@ -0,0 +1,105 @@
+# Product Principles
+
+## Purpose
+
+Defines the principles that guide product decisions.
+
+---
+
+# Principle 1
+
+## Job Tracking Comes First
+
+Jobjakt exists primarily to help users manage their job search.
+
+Every major decision should support:
+
+- Finding jobs.
+- Applying efficiently.
+- Tracking progress.
+- Improving outcomes.
+
+---
+
+# Principle 2
+
+## Career Data Is the Foundation
+
+Users should maintain one professional identity.
+
+The application should avoid:
+
+- Multiple disconnected profiles.
+- Re-entering information.
+- Duplicating career history.
+
+---
+
+# Principle 3
+
+## AI Assists, Humans Decide
+
+AI should:
+
+- Suggest.
+- Improve.
+- Analyse.
+- Accelerate.
+
+AI should not:
+
+- Replace user judgement.
+- Modify facts silently.
+- Invent experience.
+
+---
+
+# Principle 4
+
+## Simplicity Over Complexity
+
+Powerful features should remain approachable.
+
+Avoid:
+
+- Complex workflows.
+- Excessive configuration.
+- Feature overload.
+
+---
+
+# Principle 5
+
+## Progressive Disclosure
+
+Show users what they need when they need it.
+
+Example:
+
+New users:
+
+Simple CV creation.
+
+Advanced users:
+
+Custom themes, AI tools, detailed controls.
+
+---
+
+# Principle 6
+
+## Quality Over Quantity
+
+A small number of excellent features is better than many unfinished features.
+
+---
+
+# Principle 7
+
+## SaaS Ready, Not SaaS First
+
+Architecture should allow future growth.
+
+However:
+
+Do not sacrifice user experience today for hypothetical future requirements.