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/jobs/adding-jobs.md

@@ -0,0 +1,74 @@
+# Adding Jobs
+
+## Goal
+
+Adding a job should be fast.
+
+Users should not fill unnecessary forms.
+
+---
+
+# Preferred Flow
+
+## Option 1: Import URL
+
+User pastes job advert URL.
+
+System:
+
+1. Fetch page.
+2. Extract details.
+3. Create draft job.
+4. Show review screen.
+
+---
+
+# Review
+
+User confirms:
+
+- Title.
+- Company.
+- Location.
+- Description.
+- Requirements.
+
+---
+
+# Option 2: Manual Entry
+
+Fallback when import fails.
+
+Only request:
+
+Required:
+
+- Job title.
+- Company.
+- URL or description.
+
+Optional:
+
+- Salary.
+- Location.
+- Notes.
+
+---
+
+# Company Handling
+
+If company exists:
+
+Link automatically.
+
+If company does not exist:
+
+Create automatically.
+
+Do not force a separate company creation flow.
+
+---
+
+# UX Principle
+
+Adding a job should take seconds, not minutes.