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/research/reactive-resume-analysis.md

@@ -0,0 +1,50 @@
+# Reactive Resume Analysis
+
+## Purpose
+
+Study open-source CV builder architecture.
+
+---
+
+# Strengths
+
+Important concepts:
+
+- Open source.
+- Custom templates.
+- Structured data.
+- Modern UI.
+
+---
+
+# Architectural Lessons
+
+Separate:
+
+Data model.
+
+↓
+
+Renderer.
+
+↓
+
+Template.
+
+---
+
+# Relevant To Jobjakt
+
+Supports the idea:
+
+One career profile.
+
+Many outputs.
+
+---
+
+# Things To Avoid
+
+Excessive customisation complexity.
+
+Users should not need design skills.