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/technical/logging.md

@@ -0,0 +1,45 @@
+# Logging
+
+## Purpose
+
+Make debugging possible.
+
+---
+
+# Log Levels
+
+Use:
+
+Trace.
+
+Debug.
+
+Information.
+
+Warning.
+
+Error.
+
+Critical.
+
+---
+
+# Do Not Log
+
+Never log:
+
+- Passwords.
+- Tokens.
+- API keys.
+- Private documents.
+
+---
+
+# Useful Logs
+
+Include:
+
+- Operation.
+- User context where safe.
+- Error details.
+- Correlation IDs.