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/feature-comparison.md

@@ -0,0 +1,32 @@
+# Feature Comparison
+
+## Purpose
+
+Compare competitors.
+
+---
+
+| Feature | FlowCV | Novoresume | Reactive Resume | Jobjakt |
+|-|-|-|-|-|
+| Templates | | | | |
+| Live preview | | | | |
+| AI writing | | | | |
+| Job tailoring | | | | |
+| Cover letters | | | | |
+| Job tracking | | | | |
+| Portfolio | | | | |
+| Public CV | | | | |
+
+---
+
+# Goal
+
+Identify where Jobjakt wins.
+
+---
+
+Expected advantage:
+
+Competitors create documents.
+
+Jobjakt manages careers and applications.